Mulching leaves in lawns has been shown to have no negative effects and is a practice you should consider for your clients because it will improve the soil and eliminate leaves going to landfills. However, this should be done several times during the fall to prevent leaf buildup that damages turfgrass. The following is more information.
Trees will be dropping their leaves soon and it is important to prevent a heavy layer of leaves from building-up on your turf before winter. Heavy layers of tree leaves will shade the grass can smother and kill grass yet this fall. Plus tree leaf cover favors a damaging winter turf disease called snow mold. The easiest way to dispose of leaves is to simply mow them into the turf. Regular mowing during the fall will chop the leaves into small pieces and allow them to filter into the turf. Research at many universities shows that tree leaves can be mulched without any detrimental effects on the soil or turf regardless of turf or tree species. Actually, just the opposite may be true where tree leaf mulching may help improve the soil. Mulching leaves with a mower is much easier than raking, blowing, and/or vacuuming the leaves like we have done in the past. Plus it disposes of the leaves without filling up our landfills and saves our cities thousands of dollars in disposal costs. Regular mowing over dry leaves is most effective for this, but deep layers of leaves or wet leaves may require raking. Heavily wooded lots may also require leaf disposal because of the sheer volume of tree leaves.
Information adapted from the 10/25/2007 edition of the Turf Tips newsletter from Purdue University.
Showing posts with label Turf. Show all posts
Showing posts with label Turf. Show all posts
Tuesday, October 6, 2009
Thursday, August 20, 2009
Turf - Seeding Turf
With turf seeding period coming up, the following are some general guidelines to follow.
Late summer or early fall is the ideal time to seed turf grasses. The following are some points to consider for these seedings. Before seeding, address any problems that would affect turf growth (weeds, fertility, compaction). Purchase high quality seed with a recent germination test. Use improved turf varieties, with good disease resistance, adapted to our transition area (turf-type tall fescue for most general applications). Go to http://pubs.ext.vt.edu/2907/2907-1397/2907-1397.html for recommended varieties from the MD-VA turfgrass working group. Single varieties or mixtures of several varieties of the same species with similar appearance and growth habit are recommended for uniform sites. Mixtures of 2 or more species (such as turf-type tall fescue with creeping red fescue) are often used where multiple environments exist in the same property such as mixture of partially shaded and open areas. However, in a multi-species mixture, the best adapted species will be dominant. Seed into moist soil conditions or provide irrigation to achieve good germination. Soil-seed contact is critical for germination – use a packer type seeder for new seedings or complete renovations; use a slit seeder for partial renovations into existing turf. The ideal seeding period in Delaware is from the last week in August through the month of September. Grass seedling survival is greatly improved if there is 4- 6 weeks of growth before a hard frost.
Gordon Johnson, Extension Horticulture Agent, UD, Kent County
Late summer or early fall is the ideal time to seed turf grasses. The following are some points to consider for these seedings. Before seeding, address any problems that would affect turf growth (weeds, fertility, compaction). Purchase high quality seed with a recent germination test. Use improved turf varieties, with good disease resistance, adapted to our transition area (turf-type tall fescue for most general applications). Go to http://pubs.ext.vt.edu/2907/2907-1397/2907-1397.html for recommended varieties from the MD-VA turfgrass working group. Single varieties or mixtures of several varieties of the same species with similar appearance and growth habit are recommended for uniform sites. Mixtures of 2 or more species (such as turf-type tall fescue with creeping red fescue) are often used where multiple environments exist in the same property such as mixture of partially shaded and open areas. However, in a multi-species mixture, the best adapted species will be dominant. Seed into moist soil conditions or provide irrigation to achieve good germination. Soil-seed contact is critical for germination – use a packer type seeder for new seedings or complete renovations; use a slit seeder for partial renovations into existing turf. The ideal seeding period in Delaware is from the last week in August through the month of September. Grass seedling survival is greatly improved if there is 4- 6 weeks of growth before a hard frost.
Gordon Johnson, Extension Horticulture Agent, UD, Kent County
Wednesday, August 19, 2009
Turf - Core Aeration for Thatch Management
Core aeration is a good way to manage excess thatch buildup in turf. The following is more information.
Core cultivation (aeration) can be used to reduce thatch accumulation, modify the physical characteristics of thatch, and remove thatch from the soil-turf interface. A single treatment may not be as effective as dethatching in removing thatch debris, but it is less injurious and disruptive to the turf. The soil cores removed with core cultivation should be redistributed throughout the turf and thatch layer. This can be done by allowing the soil cores to dry and then dragging the cores with a steel mat or chain link fence. A dethatcher can also be used to break up soil cores. The redistribution of the soil cores into the turf modifies the physical and chemical qualities of the thatch, making it a better growing medium. Soil incorporation will also enhance thatch breakdown by improving conditions for microbial activity.
Information from "Thatch Management in Turf" Rutgers University Extension Factsheet FS740 by James A. Murphy, Ph.D., Extension Specialist in Turfgrass Mamagement
Core cultivation (aeration) can be used to reduce thatch accumulation, modify the physical characteristics of thatch, and remove thatch from the soil-turf interface. A single treatment may not be as effective as dethatching in removing thatch debris, but it is less injurious and disruptive to the turf. The soil cores removed with core cultivation should be redistributed throughout the turf and thatch layer. This can be done by allowing the soil cores to dry and then dragging the cores with a steel mat or chain link fence. A dethatcher can also be used to break up soil cores. The redistribution of the soil cores into the turf modifies the physical and chemical qualities of the thatch, making it a better growing medium. Soil incorporation will also enhance thatch breakdown by improving conditions for microbial activity.
Information from "Thatch Management in Turf" Rutgers University Extension Factsheet FS740 by James A. Murphy, Ph.D., Extension Specialist in Turfgrass Mamagement
Turf - Fall Liming
Late summer and fall are good times to apply lime to turf areas. The following are some considerations in liming lawns and turf areas.
Fall is a great time to address soil fertility issues, including liming. Recent soil tests from a reputable lab will give you some guidance on how much (if any) lime would be needed. Two pH figures are reported on a soil test report: pH and buffer pH. The pH figure tells you whether or not you need lime and the buffer pH value tells you how much is needed to reach the target pH for turf (6.0-6.5 for most turf in Delaware).
Raising soil pH is the goal of liming. If magnesium is deficient or low in the soils, those soils may benefit from the application of dolomitic limestone (Hi Mag), though magnesium availability increases with increases in pH; otherwise use calcitic lime (Hi Cal).
A few other things to keep in mind:
1. Tillage is the best way to incorporate lime when doing a new planting or complete renovation. In existing turf, core aeration is a way to move some lime into the root zone of turf and get better response to liming.
2. If surface applying lime, do not apply urea based fertilizers soon after application of the lime. Urea volatilizes much more quickly on an alkaline surface, and nitrogen is lost to the atmosphere.
3. Calcium deficiencies are extremely unlikely in Delaware and most states in the Mid-Atlantic; apply liming materials to adjust pH up, not to supply calcium (which becomes abundant at optimum pH levels). Most of our soils contain abundant amounts of available calcium, and turf uses only a small amount of calcium.
4. Gypsum does not raise soil pH. This includes waste products like ground wallboard.
Adapted from "Liming Considerations for Late Summer and Fall" Keith Diedrick and Robert Mullen in the current edition of the Crop Observation and Recommendation Network Newsletter from the Ohio State University.
Fall is a great time to address soil fertility issues, including liming. Recent soil tests from a reputable lab will give you some guidance on how much (if any) lime would be needed. Two pH figures are reported on a soil test report: pH and buffer pH. The pH figure tells you whether or not you need lime and the buffer pH value tells you how much is needed to reach the target pH for turf (6.0-6.5 for most turf in Delaware).
Raising soil pH is the goal of liming. If magnesium is deficient or low in the soils, those soils may benefit from the application of dolomitic limestone (Hi Mag), though magnesium availability increases with increases in pH; otherwise use calcitic lime (Hi Cal).
A few other things to keep in mind:
1. Tillage is the best way to incorporate lime when doing a new planting or complete renovation. In existing turf, core aeration is a way to move some lime into the root zone of turf and get better response to liming.
2. If surface applying lime, do not apply urea based fertilizers soon after application of the lime. Urea volatilizes much more quickly on an alkaline surface, and nitrogen is lost to the atmosphere.
3. Calcium deficiencies are extremely unlikely in Delaware and most states in the Mid-Atlantic; apply liming materials to adjust pH up, not to supply calcium (which becomes abundant at optimum pH levels). Most of our soils contain abundant amounts of available calcium, and turf uses only a small amount of calcium.
4. Gypsum does not raise soil pH. This includes waste products like ground wallboard.
Adapted from "Liming Considerations for Late Summer and Fall" Keith Diedrick and Robert Mullen in the current edition of the Crop Observation and Recommendation Network Newsletter from the Ohio State University.
Tuesday, August 18, 2009
Turf - Thatch
Thatch buildup can be a problem in some turf, especially bluegrass. The following is more information.
Excessive thatch accumulation is a problem on many turfgrass sites. Thatch is a layer of organic material consisting of tightly intermingled, living and dead plant tissues derived from crowns, stems, and roots. These parts of a turfgrass plant have a relatively high lignin content. Lignin is an organic compound that is highly resistant to microbial breakdown. Accumulation of a thatch layer occurs when the production of organic material (such as lignin) exceeds the rate of decomposition within the zone between green leaf tissue and the soil surface.
To assess thatch accumulation, remove a section of grass and soil from the turf using a knife, soil probe or shovel, and measure the depth of accumulated thatch. Depths greater than 1/2 inch indicate that corrective measures may be needed to reduce the thatch layer. Measurements from several locations through the turf area are needed because of the variable nature of thatch.
A thatch depth less than 1/2 inch can be beneficial because it improves turf resiliency and wear tolerance, and insulates the soil from extremes in air temperature. However, as thatch accumulates beyond 1/2 inch, the disadvantages begin to outweigh the benefits. Excessive accumulation tends to increase the susceptibility of a turf to heat, cold, and drought stress. Localized dry spots, scalping, disease, and insects may also be enhanced by excessive thatch. Such difficulties may develop as excessive thatch accumulates because the turfgrass plants will tend to have a greater portion of their crowns, rhizomes, and roots growing within the thatch rather than the soil. A weakened, poorly rooted turf is also more prone to injury and requires increased management.
Turfgrass species differ in their tendency to accumulate thatch because they have different growth rates, growth habits, and percentage of various cell wall components (Table 1). Lignin is one cell wall component that resists microbial breakdown. Vigorous species and cultivars with high lignin content accumulate thatch more readily than those with slower growth rates and lower lignin content.
Information from "Thatch Management in Turf" Rutgers University Extension Factsheet FS740 by James A. Murphy, Ph.D., Extension Specialist in Turfgrass Mamagement
Excessive thatch accumulation is a problem on many turfgrass sites. Thatch is a layer of organic material consisting of tightly intermingled, living and dead plant tissues derived from crowns, stems, and roots. These parts of a turfgrass plant have a relatively high lignin content. Lignin is an organic compound that is highly resistant to microbial breakdown. Accumulation of a thatch layer occurs when the production of organic material (such as lignin) exceeds the rate of decomposition within the zone between green leaf tissue and the soil surface.
To assess thatch accumulation, remove a section of grass and soil from the turf using a knife, soil probe or shovel, and measure the depth of accumulated thatch. Depths greater than 1/2 inch indicate that corrective measures may be needed to reduce the thatch layer. Measurements from several locations through the turf area are needed because of the variable nature of thatch.
A thatch depth less than 1/2 inch can be beneficial because it improves turf resiliency and wear tolerance, and insulates the soil from extremes in air temperature. However, as thatch accumulates beyond 1/2 inch, the disadvantages begin to outweigh the benefits. Excessive accumulation tends to increase the susceptibility of a turf to heat, cold, and drought stress. Localized dry spots, scalping, disease, and insects may also be enhanced by excessive thatch. Such difficulties may develop as excessive thatch accumulates because the turfgrass plants will tend to have a greater portion of their crowns, rhizomes, and roots growing within the thatch rather than the soil. A weakened, poorly rooted turf is also more prone to injury and requires increased management.
Turfgrass species differ in their tendency to accumulate thatch because they have different growth rates, growth habits, and percentage of various cell wall components (Table 1). Lignin is one cell wall component that resists microbial breakdown. Vigorous species and cultivars with high lignin content accumulate thatch more readily than those with slower growth rates and lower lignin content.
Information from "Thatch Management in Turf" Rutgers University Extension Factsheet FS740 by James A. Murphy, Ph.D., Extension Specialist in Turfgrass Mamagement
Sunday, August 9, 2009
Turf - Pythium Blight
We sometimes see Pythium blight in our turfgrasses in Delaware during hot humid and wet weather. The following is more information.
Pythium Blight
With the recent hot, humid weather, Pythium blight has been reported on golf and landscape turf. Pythium thrives in low or poorly drained areas, especially when the night temperatures are above 68 to 700F. For best results, improve drainage, water in the early morning hours (midnight to 8 am), avoid over-fertilization, and apply Alude, Banol, Chipco Signature, Disarm, Headway, Heritage, Insignia, Koban, Magellan, mancozeb, Prodigy, Quell, Segway, Subdue MAXX, Terraneb SP, or Terrazole, according to the manufacturer’s recommendations. Caution: Koban and Terrazole can be phytotoxic during hot weather, so follow label directions carefully and experiment on a small area before treating large areas if using either product at this time of year.
Lawn infected with Pythium blight. Photo by William M. Brown Jr., Bugwood.org.
Information from Bruce B. Clarke, Ph.D., Specialist in Turfgrass Pathology, Rutgers University from the July 23, 2009 edition of Plant & Pest Advisory, Landscape, Nursery & Turf Edition from Rutgers University.
Pythium Blight
With the recent hot, humid weather, Pythium blight has been reported on golf and landscape turf. Pythium thrives in low or poorly drained areas, especially when the night temperatures are above 68 to 700F. For best results, improve drainage, water in the early morning hours (midnight to 8 am), avoid over-fertilization, and apply Alude, Banol, Chipco Signature, Disarm, Headway, Heritage, Insignia, Koban, Magellan, mancozeb, Prodigy, Quell, Segway, Subdue MAXX, Terraneb SP, or Terrazole, according to the manufacturer’s recommendations. Caution: Koban and Terrazole can be phytotoxic during hot weather, so follow label directions carefully and experiment on a small area before treating large areas if using either product at this time of year.
Lawn infected with Pythium blight. Photo by William M. Brown Jr., Bugwood.org. Information from Bruce B. Clarke, Ph.D., Specialist in Turfgrass Pathology, Rutgers University from the July 23, 2009 edition of Plant & Pest Advisory, Landscape, Nursery & Turf Edition from Rutgers University.
Wednesday, August 5, 2009
Turf - Causes for Turf Deterioration
Before renovating a turf area, it is critical to assess why the grass declined. The following are potential causes for turf deterioration.
Causes of turf deterioration
The first step in lawn renovation is to correct the primary cause of turf deterioration. Such things as drought, excessive shade, tree root competition, poor drainage, soil compaction, inadequate fertility, acid soils, weed or insect infestation, disease, thatch build-up, improper mowing, poorly-adapted grass species and cultivars, and others may contribute to poor turf. Most of these problems can be corrected by renovation, proper turfgrass selection, and improved maintenance practices.
Shade problems
Shade problems may require removal of some trees, pruning, and planting turfgrass species that are adapted to shaded conditions. Tree roots may need pruning to reduce competition with grasses for water, air, and nutrients.
Poor drainage
Drainage problems can often be corrected by breaking-up compacted soil or through installation of drainage tile. Where surface drainage is insufficient, the site may have to be regraded so that water is removed from the site.
Soil fertility and acidity
Inadequate fertility or acid soils which can limit turf growth can be determined by testing the soil. Soil testing services are available from the Soil Testing Laboratory at the University of Delaware or through private laboratories. Kit for the soil tests are available at a nominal fee from the cooperative extension office in your county. Soil test laboratories will provide recommendations for the amounts of fertilizer and lime that need to be applied to the lawn.
Pests
Pests that cause serious turf damage need to be identified and controlled. If you cannot identify these pests, take fresh samples to your county extension office or another knowledgeable source to have them identified. The most common pest problem causing decline in Delaware turf is grubs (severa species of beetle larvae such as Japanese beetle).
Thatch
Thatch is a tightly intermingled layer of partially decomposed grass stems and roots which develops beneath the actively growing green vegetation and above the soil surface. Thatch decreases the vigor of turfgrasses by restricting the movement of water, fertilizers, and pesticides into soil. Turfgrass roots also grow into the thatch and may become desiccated as the thatch dries. Thatch builds up over a period of years and must dealt with. The best approach to managing thatch is core aeration that brings some soil up into the thatch layer. The soil will have microorganisms in it that can help the thatch to decay. Thatch removal equipment can usually be rented from garden centers or rental outlets however this is a temporary solution usually
Mowing
Mowing on most lawns should be at two inches or above and on a regular basis as long as the grass is growing. How frequently the grass is mowed depends on the growth rate of the grass. No more than one third of the total leaf surface should be removed at a given mowing. Thus, if the turf is cut at two inches, it should be mowed when it reaches a height no greater than three inches. Clippings do not need to be removed provided the lawn is mowed on a regular basis. All mowing equipment needs to be sharpened and adjusted periodically.
Species and management
Unadapted species and improper management are perhaps the most common causes of turfgrass deterioration. Species and management must be adapted to the conditions present at the site. Other problems include the use of inferior turfgrass cultivars and poor quality seed. Once the reasons for lawn deterioration are recognized and steps are taken to correct the problems, the renovation program can begin. The following three programs are designed to fit most renovation situations. Some operations may need to be altered or omitted depending on the individual situation.
Information adapted from a fact sheet from Penn State University http://cropsoil.psu.edu/Extension/Turf/pdf/ec412.pdf
Causes of turf deterioration
The first step in lawn renovation is to correct the primary cause of turf deterioration. Such things as drought, excessive shade, tree root competition, poor drainage, soil compaction, inadequate fertility, acid soils, weed or insect infestation, disease, thatch build-up, improper mowing, poorly-adapted grass species and cultivars, and others may contribute to poor turf. Most of these problems can be corrected by renovation, proper turfgrass selection, and improved maintenance practices.
Shade problems
Shade problems may require removal of some trees, pruning, and planting turfgrass species that are adapted to shaded conditions. Tree roots may need pruning to reduce competition with grasses for water, air, and nutrients.
Poor drainage
Drainage problems can often be corrected by breaking-up compacted soil or through installation of drainage tile. Where surface drainage is insufficient, the site may have to be regraded so that water is removed from the site.
Soil fertility and acidity
Inadequate fertility or acid soils which can limit turf growth can be determined by testing the soil. Soil testing services are available from the Soil Testing Laboratory at the University of Delaware or through private laboratories. Kit for the soil tests are available at a nominal fee from the cooperative extension office in your county. Soil test laboratories will provide recommendations for the amounts of fertilizer and lime that need to be applied to the lawn.
Pests
Pests that cause serious turf damage need to be identified and controlled. If you cannot identify these pests, take fresh samples to your county extension office or another knowledgeable source to have them identified. The most common pest problem causing decline in Delaware turf is grubs (severa species of beetle larvae such as Japanese beetle).
Thatch
Thatch is a tightly intermingled layer of partially decomposed grass stems and roots which develops beneath the actively growing green vegetation and above the soil surface. Thatch decreases the vigor of turfgrasses by restricting the movement of water, fertilizers, and pesticides into soil. Turfgrass roots also grow into the thatch and may become desiccated as the thatch dries. Thatch builds up over a period of years and must dealt with. The best approach to managing thatch is core aeration that brings some soil up into the thatch layer. The soil will have microorganisms in it that can help the thatch to decay. Thatch removal equipment can usually be rented from garden centers or rental outlets however this is a temporary solution usually
Mowing
Mowing on most lawns should be at two inches or above and on a regular basis as long as the grass is growing. How frequently the grass is mowed depends on the growth rate of the grass. No more than one third of the total leaf surface should be removed at a given mowing. Thus, if the turf is cut at two inches, it should be mowed when it reaches a height no greater than three inches. Clippings do not need to be removed provided the lawn is mowed on a regular basis. All mowing equipment needs to be sharpened and adjusted periodically.
Species and management
Unadapted species and improper management are perhaps the most common causes of turfgrass deterioration. Species and management must be adapted to the conditions present at the site. Other problems include the use of inferior turfgrass cultivars and poor quality seed. Once the reasons for lawn deterioration are recognized and steps are taken to correct the problems, the renovation program can begin. The following three programs are designed to fit most renovation situations. Some operations may need to be altered or omitted depending on the individual situation.
Information adapted from a fact sheet from Penn State University http://cropsoil.psu.edu/Extension/Turf/pdf/ec412.pdf
Saturday, August 1, 2009
Turf - Brown Patch Now Appearing
Brown patch season has arrived in turf across Delaware. The following is more information.
Brown Patch disease is active now after recent rains and high night humidity. Turf-type tall fescue and others turf species are susceptible when the weather turns hazy, hot and humid and night temperatures stay in the 70's. This disease, caused by the fungus Rhizoctonia solani, has been present for the past week on landscape turf and golf courses. To reduce the incidence and severity of brown patch for golf courses and other highly managed turf, avoid summer avoid large applications of quick release nitrogen sources (e.g., not more than ¼ lb actual N/1000 sq. ft) during hot weather, irrigate between midnight and 8 a.m. to minimize the leaf wetness period, and spray turf now with Armada, Banner (preventive only), Chipco 26GT, chlorothalonil, Compass, ConSyst, Curalan, Disarm, Eagle, Endorse, Headway, Heritage, Insignia, mancozeb, Medallion, Prostar, Spectro, Tartan, thiophanate-methyl or Trinity per manufacturer's recommendations.
Information from Bob Mulrooney, Extension Plant Pathologist, UD.
Brown Patch disease is active now after recent rains and high night humidity. Turf-type tall fescue and others turf species are susceptible when the weather turns hazy, hot and humid and night temperatures stay in the 70's. This disease, caused by the fungus Rhizoctonia solani, has been present for the past week on landscape turf and golf courses. To reduce the incidence and severity of brown patch for golf courses and other highly managed turf, avoid summer avoid large applications of quick release nitrogen sources (e.g., not more than ¼ lb actual N/1000 sq. ft) during hot weather, irrigate between midnight and 8 a.m. to minimize the leaf wetness period, and spray turf now with Armada, Banner (preventive only), Chipco 26GT, chlorothalonil, Compass, ConSyst, Curalan, Disarm, Eagle, Endorse, Headway, Heritage, Insignia, mancozeb, Medallion, Prostar, Spectro, Tartan, thiophanate-methyl or Trinity per manufacturer's recommendations.
Information from Bob Mulrooney, Extension Plant Pathologist, UD.
Tuesday, July 28, 2009
Turf - Grub Control With Beneficial Nematodes
The following is information on grub control in lawns using beneficial nematodes from the University of Maryland.
Non –Chemical Control of Grubs in Lawns
The interest in non-chemical control of white grubs in lawns is increasing. Japanese beetles are laying eggs in the soil in late July through early August. The newly hatching larvae will be very susceptible to control using beneficial nematodes. Nematodes are microscopic, non-segmented worms which occur naturally in soil all over the world. Beneficial nematodes attack soil dwelling insects and leave plants alone. These predators enter the host through body openings or by penetration of the body wall. Beneficial nematodes are considered safe and EPA has waived the registration requirements for application.
When Heterorhabditis bacteriophora (Hb) nematodes sense the temperature and carbon dioxide emissions of soil-borne insects, they move toward their prey and enter the pest through its body openings. The nematodes carry an associated symbiotic bacterium (Xenorhabdus species) that kills insects within 48 hours. The bacteria is harmless to humans and other organisms and cannot live freely in nature. Several generations of nematodes may live and breed within the dead pest before emerging and seeking more pests in the soil.
Heterorhabditis bacteriophora nematodes are a good choice for white grub control at this time of year. The key is that they need a lot of water to survive in turf areas. Irrigate the day of the application or apply during periods of rain. The lawn area must be keep moist for a couple of days after an application to keep the nematodes alive. Infected grubs become slimy and discolored and turn from white-beige to red-brown within 3 to 5 days after application. Nematodes leave the grub when they reach the infectious third stage to search for new larvae. The nematode population will slowly decrease when no new hosts are present.
Checking to Make Sure Nematodes Are Alive is Essential: It’s critical when using beneficial nematodes to check the population to make sure they are alive at application time. Draw off a small sample and examine the water with nematodes under a magnification of 20X. Live nematodes will be slightly curved and moving. Dead nematodes are still and straight as a board.
Information from Stanton Gill, University of Maryland http://www.ipmnet.umd.edu/09Jul24L.pdf
Non –Chemical Control of Grubs in Lawns
The interest in non-chemical control of white grubs in lawns is increasing. Japanese beetles are laying eggs in the soil in late July through early August. The newly hatching larvae will be very susceptible to control using beneficial nematodes. Nematodes are microscopic, non-segmented worms which occur naturally in soil all over the world. Beneficial nematodes attack soil dwelling insects and leave plants alone. These predators enter the host through body openings or by penetration of the body wall. Beneficial nematodes are considered safe and EPA has waived the registration requirements for application.
When Heterorhabditis bacteriophora (Hb) nematodes sense the temperature and carbon dioxide emissions of soil-borne insects, they move toward their prey and enter the pest through its body openings. The nematodes carry an associated symbiotic bacterium (Xenorhabdus species) that kills insects within 48 hours. The bacteria is harmless to humans and other organisms and cannot live freely in nature. Several generations of nematodes may live and breed within the dead pest before emerging and seeking more pests in the soil.
Heterorhabditis bacteriophora nematodes are a good choice for white grub control at this time of year. The key is that they need a lot of water to survive in turf areas. Irrigate the day of the application or apply during periods of rain. The lawn area must be keep moist for a couple of days after an application to keep the nematodes alive. Infected grubs become slimy and discolored and turn from white-beige to red-brown within 3 to 5 days after application. Nematodes leave the grub when they reach the infectious third stage to search for new larvae. The nematode population will slowly decrease when no new hosts are present.
Checking to Make Sure Nematodes Are Alive is Essential: It’s critical when using beneficial nematodes to check the population to make sure they are alive at application time. Draw off a small sample and examine the water with nematodes under a magnification of 20X. Live nematodes will be slightly curved and moving. Dead nematodes are still and straight as a board.
Information from Stanton Gill, University of Maryland http://www.ipmnet.umd.edu/09Jul24L.pdf
Friday, July 24, 2009
Turf - Weather Changes Mean Added Stress
Following a cool, wet, spring, turf will suffer challenges in the hot summer during dry periods. The following is an article on the subject from Rutgers University. Although it is focusing on golf courses and putting greens, the same effects will be seen on lawns and other turfgrass areas.
As the weather turns, so goes the turfgrass. Beautiful fall-like weather (I know it’s July) over the July fourth weekend really changed the dynamics on golf course putting greens in our region. Endless days of rain and overcast skies through May and June have been replaced with low humidity, high skies, cool breezes and moderate to high temperatures. Superintendents have been talking about super-saturated root zones and poor root mass for several weeks now and worrying about an abrupt change to summer heat. Those plants compromised by the wet spring were suddenly faced with a significant increase in transpiration demand. Over the last few weeks, we have seen plenty of poorly performing turfgrass on tough sites, but now we are starting to see plants that simply couldn’t keep up with the change in the weather. Putting green samples of both annual bluegrass and bentgrass are being submitted to the laboratory at a vigorous pace (25 this week). All of them have the same symptoms – slight thinning, poor growth and leaf tip scorch. The submissions came from Rehoboth Beach, Delaware to the south and out to the tip of Long Island to the north. Some samples, of course, look worse than others. Those where we find slight fungal insults - like Pythium root dysfunction or Curvularia fading out - or site related issues - like shade, compaction, or thatch - have more severe symptom expression. All of the samples; however, regardless of the source have the leaf tip scorch symptom in common. Pay close attention to the moisture needs of your turf areas moving forward and keep a careful eye towards stress related disease. There was a long period of wet and cloudy weather this spring and I think our turf may need to feel a little pain before it overcomes it.
Adapted from information by Richard J. Buckley, Director, Soil Testing and Plant Diagnostic
Services, Rutgers University http://njaes.rutgers.edu/pubs/plantandpestadvisory/2009/ln070909.pdf
As the weather turns, so goes the turfgrass. Beautiful fall-like weather (I know it’s July) over the July fourth weekend really changed the dynamics on golf course putting greens in our region. Endless days of rain and overcast skies through May and June have been replaced with low humidity, high skies, cool breezes and moderate to high temperatures. Superintendents have been talking about super-saturated root zones and poor root mass for several weeks now and worrying about an abrupt change to summer heat. Those plants compromised by the wet spring were suddenly faced with a significant increase in transpiration demand. Over the last few weeks, we have seen plenty of poorly performing turfgrass on tough sites, but now we are starting to see plants that simply couldn’t keep up with the change in the weather. Putting green samples of both annual bluegrass and bentgrass are being submitted to the laboratory at a vigorous pace (25 this week). All of them have the same symptoms – slight thinning, poor growth and leaf tip scorch. The submissions came from Rehoboth Beach, Delaware to the south and out to the tip of Long Island to the north. Some samples, of course, look worse than others. Those where we find slight fungal insults - like Pythium root dysfunction or Curvularia fading out - or site related issues - like shade, compaction, or thatch - have more severe symptom expression. All of the samples; however, regardless of the source have the leaf tip scorch symptom in common. Pay close attention to the moisture needs of your turf areas moving forward and keep a careful eye towards stress related disease. There was a long period of wet and cloudy weather this spring and I think our turf may need to feel a little pain before it overcomes it.
Adapted from information by Richard J. Buckley, Director, Soil Testing and Plant Diagnostic
Services, Rutgers University http://njaes.rutgers.edu/pubs/plantandpestadvisory/2009/ln070909.pdf
Saturday, July 4, 2009
Turf - Controlling Crabgrass Breaks
The following is general information on controlling crabgrass breaks in turf.
With the heavy rains and cool weather conditions this spring I’m expecting that a significant number of preemergence herbicide applications will fail. Above average rainfall will result in an increased dissipation of preemergence herbicide out of the crabgrass germination zone while the cool temperatures are prolonging the crabgrass germination cycle. As always, maintaining a dense and healthy turfgrass stand throughout the summer is our first and best line of defense to prevent preemergence crabgrass herbicide failures. However, if summer stresses which thin and weaken the turfgrass stand occur; postemergence herbicides may need to be utilized to control crabgrass that germinates later in the season.
Both Acclaim Extra and Drive herbicides can be used to control crabgrass breaks. However, crabgrass cannot be too large (ideally less than 2 tillers, but no more than 4 tillers). Both herbicides are most effective when applied to young actively growing crabgrass in good soil moisture conditions. Applying either herbicide to sites under drought and/or heat stress may result in reduced control of crabgrass and other summer annual grasses as well as increased potential for turfgrass injury. Weed control with both herbicides is most effective when applied with flat fan nozzles producing a fine spray droplet. I do not recommended the use of flood jets with either herbicide. Both herbicides may be applied in combination with residual preemergence herbicides. However, applying residual herbicides late in the season may interfere with overseeding operations in late summer/fall.
Information adapted from an article from Dr. Steve Hart, Extension Weed Science Specialist, Rutgers University.
With the heavy rains and cool weather conditions this spring I’m expecting that a significant number of preemergence herbicide applications will fail. Above average rainfall will result in an increased dissipation of preemergence herbicide out of the crabgrass germination zone while the cool temperatures are prolonging the crabgrass germination cycle. As always, maintaining a dense and healthy turfgrass stand throughout the summer is our first and best line of defense to prevent preemergence crabgrass herbicide failures. However, if summer stresses which thin and weaken the turfgrass stand occur; postemergence herbicides may need to be utilized to control crabgrass that germinates later in the season.
Both Acclaim Extra and Drive herbicides can be used to control crabgrass breaks. However, crabgrass cannot be too large (ideally less than 2 tillers, but no more than 4 tillers). Both herbicides are most effective when applied to young actively growing crabgrass in good soil moisture conditions. Applying either herbicide to sites under drought and/or heat stress may result in reduced control of crabgrass and other summer annual grasses as well as increased potential for turfgrass injury. Weed control with both herbicides is most effective when applied with flat fan nozzles producing a fine spray droplet. I do not recommended the use of flood jets with either herbicide. Both herbicides may be applied in combination with residual preemergence herbicides. However, applying residual herbicides late in the season may interfere with overseeding operations in late summer/fall.
Information adapted from an article from Dr. Steve Hart, Extension Weed Science Specialist, Rutgers University.
Friday, July 3, 2009
Turf - Drive for Postemergence Crabgrass Control
Crabgrass breaks are occurring in landscapes this year due to the previous wet weather. The following is information on using quinclorac (Drive) herbicide for postemergence crabgrass control.
Drive Herbicide
Drive herbicide (quinclorac) is safe on Kentucky bluegrass, perennial ryegrass and tall fescue. Consult the label carefully for use on bentgrasses and fine fescue. Drive can be effective on 2-4 tillered crabgrass but for the most consistent control Drive should be applied to crabgrass prior to two tillers. Drive is also highly active on large multi-tillered crabgrass but only when it has entered its reproductive phase (visable seedheads). Drive will not control goosegrass. Drive is tank-mix compatible with broadleaf weed herbicides. For optimum activity Drive must be applied with methylated seed oil (MSO). Two formulations are available: Drive 75 DF and a new liquid formulation Drive XLR8 1.5 L. In some studies we have observed more consistent crabgrass control with Drive XLR8 compared to Drive 75 DF.
Combination Products: A number of combination products are currently being marketed such as Q4, Quincept, and Onetime, which contain Drive in combination with broadleaf weed herbicides or in the case of Q4 also contain sulfentrazone for suppression of yellow nutsedge. Consult labels carefully to determine if a spray adjuvant is recommended. Also determine the use rate of quinclorac (the active ingredient in Drive) you will be applying. Applying quinclorac at less than 0.75 lbs ai/A and/or without a spray adjuvant such as methylated seed oil may reduce the consistency of crabgrass control especially if the growth stage has exceeded one-tiller.
Information from Dr. Stephen E. Hart, Associate Extension Specialist, Weed Science, Rutgers University
Drive Herbicide
Drive herbicide (quinclorac) is safe on Kentucky bluegrass, perennial ryegrass and tall fescue. Consult the label carefully for use on bentgrasses and fine fescue. Drive can be effective on 2-4 tillered crabgrass but for the most consistent control Drive should be applied to crabgrass prior to two tillers. Drive is also highly active on large multi-tillered crabgrass but only when it has entered its reproductive phase (visable seedheads). Drive will not control goosegrass. Drive is tank-mix compatible with broadleaf weed herbicides. For optimum activity Drive must be applied with methylated seed oil (MSO). Two formulations are available: Drive 75 DF and a new liquid formulation Drive XLR8 1.5 L. In some studies we have observed more consistent crabgrass control with Drive XLR8 compared to Drive 75 DF.
Combination Products: A number of combination products are currently being marketed such as Q4, Quincept, and Onetime, which contain Drive in combination with broadleaf weed herbicides or in the case of Q4 also contain sulfentrazone for suppression of yellow nutsedge. Consult labels carefully to determine if a spray adjuvant is recommended. Also determine the use rate of quinclorac (the active ingredient in Drive) you will be applying. Applying quinclorac at less than 0.75 lbs ai/A and/or without a spray adjuvant such as methylated seed oil may reduce the consistency of crabgrass control especially if the growth stage has exceeded one-tiller.
Information from Dr. Stephen E. Hart, Associate Extension Specialist, Weed Science, Rutgers University
Tuesday, June 30, 2009
Turf - Grub Control
The following is a good article on grub control in turf from Rutgers University.
Soon they will be flying again, the adults of those pesky white grubs, like oriental beetle, Japanese beetle, masked chafers, Asiatic garden beetle, European chafer, and green June beetle. Adult oriental beetles typically peak in abundance from late-June into early July, followed by Japanese beetles about mid-July. Peak adult activity means peak egg-laying which is followed 2-3 weeks later by peak hatching off the eggs.
The young first stage larvae are the stage that is the most susceptible to insecticides, and numbers of this stage peak from mid-July to early August. If an applicator chooses to preventively treat turf for white grubs, the ideal time to do an application would be somewhat earlier than the time of peak first larval stage density to allow the insecticidal active ingredient to reach peak concentration in the target zone, i.e., the thatch and top 1-2 inches of the soil. How much earlier depends on how fast the active ingredient will move through the thatch. Generally, the more water soluble an active ingredient is, the faster it will move downwards into the soil with rain and irrigation water.
However, the application window of most of the newer white grub insecticides is rather wide and many of them can be applied from May into August with little differences in control rates. Reasons for these wide windows are that (1) the active ingredient has a long half-life in the soil allowing earlier applications, (2) the second larval stage of the white grubs is generally still very susceptible to the active ingredient allowing later applications, and/or (3) the recommended application rates are high enough to compensate for 1-3 months of slow active ingredient breakdown in the soil or the lower susceptibility of the larger white grubs.
Imidacloprid (Merit) and thiamethoxam (Meridian) seem to be very effective when applied from May through August, clothianidin (Arena) even from May into September, halofenozide (Mach2) from June through August, and chlorantraniliprole (Acelepryn) from April at least into mid-August.
An interesting new finding is that chlorantraniliprole (Acelepryn) actually tends to be more effective when applied earlier. Due to its very low water solubility (> 5 ppm) chlorantraniliprole takes around 50 days to reach peak concentration in the thatch and 100 days to reach peak concentration in the soil. However, chlorantraniliprole clearly is effective enough to compensate for this slow movement. Averaged over dozens of research trials for each application timing, chlorantraniliprole at 0.1 lb active ingredient per acre applied in April, May, June, July, and August has provided 96%, 94%, 91%, 88%, and 79% control, respectively, of all the major white grub species. However, even the 79% control in August is at least as good as what one can expect with an application of trichlorfon (Dylox) and certainly good enough to suppress white grub damage.
As always, keep in mind that repeated application of the same insecticide class year after year could lead to insecticide resistance and/or enhanced microbial degradation of the compound. Enhanced microbial degradation would be particularly problematic if the compound is applied several weeks to months before the presence of the target (i.e., before July). Therefore regularly rotate insecticides from different insecticide classes. Earlier applications are also more likely to interfere with naturally occurring predators and parasites of white grubs and other turfgrass insect pests. Applications before July or even June should therefore be reserved for cases where there is some additional benefit such as suppression of other insect pests with damage potential.
Reprinted from "Timing of White Grub Treatments in Turfgrass" by Albrecht M. Koppenhöfer, Ph.D., Specialist in Turfgrass Entomology in the June 11, 2009 edition of the Plant and Pest Advisory, Landscape, Nursery, and Turf Edition from Rutgers University http://njaes.rutgers.edu/pubs/plantandpestadvisory/2009/ln061109.pdf
Soon they will be flying again, the adults of those pesky white grubs, like oriental beetle, Japanese beetle, masked chafers, Asiatic garden beetle, European chafer, and green June beetle. Adult oriental beetles typically peak in abundance from late-June into early July, followed by Japanese beetles about mid-July. Peak adult activity means peak egg-laying which is followed 2-3 weeks later by peak hatching off the eggs.
The young first stage larvae are the stage that is the most susceptible to insecticides, and numbers of this stage peak from mid-July to early August. If an applicator chooses to preventively treat turf for white grubs, the ideal time to do an application would be somewhat earlier than the time of peak first larval stage density to allow the insecticidal active ingredient to reach peak concentration in the target zone, i.e., the thatch and top 1-2 inches of the soil. How much earlier depends on how fast the active ingredient will move through the thatch. Generally, the more water soluble an active ingredient is, the faster it will move downwards into the soil with rain and irrigation water.
However, the application window of most of the newer white grub insecticides is rather wide and many of them can be applied from May into August with little differences in control rates. Reasons for these wide windows are that (1) the active ingredient has a long half-life in the soil allowing earlier applications, (2) the second larval stage of the white grubs is generally still very susceptible to the active ingredient allowing later applications, and/or (3) the recommended application rates are high enough to compensate for 1-3 months of slow active ingredient breakdown in the soil or the lower susceptibility of the larger white grubs.
Imidacloprid (Merit) and thiamethoxam (Meridian) seem to be very effective when applied from May through August, clothianidin (Arena) even from May into September, halofenozide (Mach2) from June through August, and chlorantraniliprole (Acelepryn) from April at least into mid-August.
An interesting new finding is that chlorantraniliprole (Acelepryn) actually tends to be more effective when applied earlier. Due to its very low water solubility (> 5 ppm) chlorantraniliprole takes around 50 days to reach peak concentration in the thatch and 100 days to reach peak concentration in the soil. However, chlorantraniliprole clearly is effective enough to compensate for this slow movement. Averaged over dozens of research trials for each application timing, chlorantraniliprole at 0.1 lb active ingredient per acre applied in April, May, June, July, and August has provided 96%, 94%, 91%, 88%, and 79% control, respectively, of all the major white grub species. However, even the 79% control in August is at least as good as what one can expect with an application of trichlorfon (Dylox) and certainly good enough to suppress white grub damage.
As always, keep in mind that repeated application of the same insecticide class year after year could lead to insecticide resistance and/or enhanced microbial degradation of the compound. Enhanced microbial degradation would be particularly problematic if the compound is applied several weeks to months before the presence of the target (i.e., before July). Therefore regularly rotate insecticides from different insecticide classes. Earlier applications are also more likely to interfere with naturally occurring predators and parasites of white grubs and other turfgrass insect pests. Applications before July or even June should therefore be reserved for cases where there is some additional benefit such as suppression of other insect pests with damage potential.
Reprinted from "Timing of White Grub Treatments in Turfgrass" by Albrecht M. Koppenhöfer, Ph.D., Specialist in Turfgrass Entomology in the June 11, 2009 edition of the Plant and Pest Advisory, Landscape, Nursery, and Turf Edition from Rutgers University http://njaes.rutgers.edu/pubs/plantandpestadvisory/2009/ln061109.pdf
Sunday, June 21, 2009
Turf - Grub Control Considerations
Preventative grub control is best done on small larvae after eggs have hatched in July. Curative treatments can be done later if infestations are found. The following are some grub treatmetn decision considerations from Rutgers University.
That time of the year is fast approaching. The beetles will be flying and checking out your turf for nice egg-laying sites. Oriental beetles will come first followed by the more in-your-face Japanese beetles within the next three weeks. This is the time to think about white grub management. The question is whether to apply a preventive application that is more expensive and often not necessary, or to take your chances and apply a curative application later if monitoring suggests damaging grub densities.
July would be the best time to bring out any preventive application. However, such preventive applications should be restricted to areas with very low damage threshold and tolerance, areas with a history of white grub infestations, and areas with high beetle activity (egg-laying) in June-July. Remember that the dominant white grub species may vary in Delaware and may include the oriental beetle, Japanese beetle and Asiatic garden beetle. Other species like northern masked chafer and green June beetle can also cause damage in some locations. Keep in mind that species attacking turf can vary to some extent from year to year and can vary dramatically from site to site.
Information adapted from "To Treat or not to Treat: Update on Preventive White Grub Treatments" by Albrecht M. Koppenhöfer, Ph.D., Specialist in Turfgrass Entomology, Rutgers University in the June 26, 2008 edition of the Plant and Pest Advisory, Landscape, Nursery & Turf Edition, Rutgers Cooperative Extension.
That time of the year is fast approaching. The beetles will be flying and checking out your turf for nice egg-laying sites. Oriental beetles will come first followed by the more in-your-face Japanese beetles within the next three weeks. This is the time to think about white grub management. The question is whether to apply a preventive application that is more expensive and often not necessary, or to take your chances and apply a curative application later if monitoring suggests damaging grub densities.
July would be the best time to bring out any preventive application. However, such preventive applications should be restricted to areas with very low damage threshold and tolerance, areas with a history of white grub infestations, and areas with high beetle activity (egg-laying) in June-July. Remember that the dominant white grub species may vary in Delaware and may include the oriental beetle, Japanese beetle and Asiatic garden beetle. Other species like northern masked chafer and green June beetle can also cause damage in some locations. Keep in mind that species attacking turf can vary to some extent from year to year and can vary dramatically from site to site.
Information adapted from "To Treat or not to Treat: Update on Preventive White Grub Treatments" by Albrecht M. Koppenhöfer, Ph.D., Specialist in Turfgrass Entomology, Rutgers University in the June 26, 2008 edition of the Plant and Pest Advisory, Landscape, Nursery & Turf Edition, Rutgers Cooperative Extension.
Monday, June 8, 2009
Turf - Brown Patch Season Coming Up
Brown patch season will be coming up in turf later in June. The following is a short reminder article.
Brown Patch
This disease, caused by the fungus Rhizoctonia solani, will be starting to develop later in June on turf. To reduce the incidence and severity of brown patch, avoid applying too much nitrogen (e.g., not more than ¼ lb actual N/1000 sq. ft) during hot weather, irrigate between midnight and 8 a.m. to minimize the leaf wetness period, and spray turf now with Armada, Banner (preventive only), Chipco 26GT, chlorothalonil, Compass, ConSyst, Curalan, Disarm, Eagle, Endorse, Headway, Heritage, Insignia, mancozeb, Medallion, ProStar, Spectro, Tartan, thiophanate-methyl, Touche or Tourney per manufacturer’s recommendations.
Information from Bruce B. Clarke, Ph.D., Specialist in Turfgrass Pathology, Rutgers University
Brown Patch
This disease, caused by the fungus Rhizoctonia solani, will be starting to develop later in June on turf. To reduce the incidence and severity of brown patch, avoid applying too much nitrogen (e.g., not more than ¼ lb actual N/1000 sq. ft) during hot weather, irrigate between midnight and 8 a.m. to minimize the leaf wetness period, and spray turf now with Armada, Banner (preventive only), Chipco 26GT, chlorothalonil, Compass, ConSyst, Curalan, Disarm, Eagle, Endorse, Headway, Heritage, Insignia, mancozeb, Medallion, ProStar, Spectro, Tartan, thiophanate-methyl, Touche or Tourney per manufacturer’s recommendations.
Information from Bruce B. Clarke, Ph.D., Specialist in Turfgrass Pathology, Rutgers University
Wednesday, June 3, 2009
Turf - White Clover
This has been a good year for white clover in turf and it is in bloom across the state. The following are some pictures. Control is not necessary in low maintenance turf as it can be beneficial. In high management turf an lawns, certain broadleaf herbicides will provide control (see previous post).
Gordon Johnson, Extension Horticulture Agent, UD, Kent County
Gordon Johnson, Extension Horticulture Agent, UD, Kent County
Turf - White Clover Year
It has been a good year for white clover in turf. It is in bloom across the state. The following is more information on white clover an its control.
White clover is in bloom across the state at this time. White clover produces significant amounts of hard seed that remains in the soil for a long time. Years with cool moist springs and mild summers favor white clover germination and proliferation of existing plants. White Clover is a low growing stoloniferous perennial legume. It can be beneficial in low maintenance turf because it fixes N and compliments the grass. However, in high maintenance turf and residential lawns it is viewed a weed because it is often short lived and seed heads attract bees. Identify by the compound leaves composed of 3 unstalked leaflets less than 1 inch long with white crescent shaped marks. Blooms will be 1 inch diameter white balls starting to appear in May. White clover is most prevalent in turf receiving limited nitrogen fertilization and tolerates low mowing. Control white clover in turf by increasing nitrogen fertilization, cutting higher, and managing for a dense grass stand. Postemergence broadleaf herbicides effective on white clover including triclopyr, clopyralid (clopyralid is not for use in residential turf), quinclorac, and fluroxypyr. Broadleaf herbicide mixtures that include 2,4-D, dicamba, MCPP, or MCPA in combination or with one or more of the materials previously listed are also effective.
Gordon Johnson, Extension Horticultural Agent, UD, Kent County
White clover is in bloom across the state at this time. White clover produces significant amounts of hard seed that remains in the soil for a long time. Years with cool moist springs and mild summers favor white clover germination and proliferation of existing plants. White Clover is a low growing stoloniferous perennial legume. It can be beneficial in low maintenance turf because it fixes N and compliments the grass. However, in high maintenance turf and residential lawns it is viewed a weed because it is often short lived and seed heads attract bees. Identify by the compound leaves composed of 3 unstalked leaflets less than 1 inch long with white crescent shaped marks. Blooms will be 1 inch diameter white balls starting to appear in May. White clover is most prevalent in turf receiving limited nitrogen fertilization and tolerates low mowing. Control white clover in turf by increasing nitrogen fertilization, cutting higher, and managing for a dense grass stand. Postemergence broadleaf herbicides effective on white clover including triclopyr, clopyralid (clopyralid is not for use in residential turf), quinclorac, and fluroxypyr. Broadleaf herbicide mixtures that include 2,4-D, dicamba, MCPP, or MCPA in combination or with one or more of the materials previously listed are also effective.
Gordon Johnson, Extension Horticultural Agent, UD, Kent County
Saturday, May 30, 2009
Landscape and Turf - Ants
The following is information on ants in landscapes or turf.
BLACK PAVEMENT ANTS (Tetramorium caespitum) are the most likely culprits if the mounds are relatively small, measuring 2-4" across. BLACK FIELD ANTS (Formica subsericea) are the architects if the mounds are large and relatively flat, measuring 1-3' across and only a few inches tall. Pyramidal mounds that are 1-3' across and 1-2' tall are engineered by ALLEGHENY MOUND ANTS (F. excectoides).
Black pavement ants are small and have pale legs, a brown to black thorax, and a black abdomen. Their habit of locating their underground colonies beside or beneath sidewalks gives rise to their common name. The ants scavenge for a wide variety of food including live and dead insects, honeydew from aphids, grease, etc. The ants are very protective of their feeding territory, and very intolerant of nearby colonies. They are well-known for their bare-tarsal brawls with battles sometime spilling across the entire width of sidewalks.
Black field ants and Allegheny mound ants are both relatively large with foraging workers measuring around 1/4" in length. Both are also associated with aphids, or other plant-sucking insects. The ants protect the sucking insects by fending off predators. In return, the sucking insects provide the ants with high energy carbohydrates in the form of honeydew.
Allegheny mound ants are one of the true mound-builders of the ant world. Their pyramidal mounds rise conspicuously above the surrounding landscape. Mound ants range in color from chestnut red, to black, to a combination of red and black. The ants are very aggressive, and they can use their powerful mandibles to deliver a noticeable pinching bite to a probing finger. However, their threat to people is inconsequential compared to their impact on plants. Mound ants are capable of killing small bushes and trees by injecting formic acid into wounds created by their mandibles. They use this capability to clear plants that shade their mounds. All vegetation, with the exception of large trees, may be killed within 40-50' of large, well-established mounds.
Black field ants are much less accomplished mound-builders. They form large, low-profile mounds of loose soil. These ants do not inject formic acid into plants, so they are not direct plant killers. However, they often heap soil over low-growing plants and they will pile soil high onto plant stems. Their plant-smothering mounds have been known to cause plants to decline and die. In particular, they are sometimes considered a serious pest of turfgrass. These large black ants are also very aggressive, and they will attempt to bite using their powerful, well developed mandibles.
Although both Allegheny mound ants and black field ants feed on honeydew produced by plant-sucking insects, they are also very effective scavengers and predators. The same is true of black pavement ants. The ants may be observed dragging live or dead cuisine back to their mounds to be surgically dismantled for protein. Since these ants are considered beneficial, management efforts should focus on dissuasion. For example, the pavement ants and field ants loathe thick, high-cut turfgrass. Repeated destruction of the mound ants abode can persuade them to locate elsewhere.
Information from the Ohio State Unibersity Buckeye Yard and Garden On-Line
http://bygl.osu.edu/
BLACK PAVEMENT ANTS (Tetramorium caespitum) are the most likely culprits if the mounds are relatively small, measuring 2-4" across. BLACK FIELD ANTS (Formica subsericea) are the architects if the mounds are large and relatively flat, measuring 1-3' across and only a few inches tall. Pyramidal mounds that are 1-3' across and 1-2' tall are engineered by ALLEGHENY MOUND ANTS (F. excectoides).
Black pavement ants are small and have pale legs, a brown to black thorax, and a black abdomen. Their habit of locating their underground colonies beside or beneath sidewalks gives rise to their common name. The ants scavenge for a wide variety of food including live and dead insects, honeydew from aphids, grease, etc. The ants are very protective of their feeding territory, and very intolerant of nearby colonies. They are well-known for their bare-tarsal brawls with battles sometime spilling across the entire width of sidewalks.
Black field ants and Allegheny mound ants are both relatively large with foraging workers measuring around 1/4" in length. Both are also associated with aphids, or other plant-sucking insects. The ants protect the sucking insects by fending off predators. In return, the sucking insects provide the ants with high energy carbohydrates in the form of honeydew.
Allegheny mound ants are one of the true mound-builders of the ant world. Their pyramidal mounds rise conspicuously above the surrounding landscape. Mound ants range in color from chestnut red, to black, to a combination of red and black. The ants are very aggressive, and they can use their powerful mandibles to deliver a noticeable pinching bite to a probing finger. However, their threat to people is inconsequential compared to their impact on plants. Mound ants are capable of killing small bushes and trees by injecting formic acid into wounds created by their mandibles. They use this capability to clear plants that shade their mounds. All vegetation, with the exception of large trees, may be killed within 40-50' of large, well-established mounds.
Black field ants are much less accomplished mound-builders. They form large, low-profile mounds of loose soil. These ants do not inject formic acid into plants, so they are not direct plant killers. However, they often heap soil over low-growing plants and they will pile soil high onto plant stems. Their plant-smothering mounds have been known to cause plants to decline and die. In particular, they are sometimes considered a serious pest of turfgrass. These large black ants are also very aggressive, and they will attempt to bite using their powerful, well developed mandibles.
Although both Allegheny mound ants and black field ants feed on honeydew produced by plant-sucking insects, they are also very effective scavengers and predators. The same is true of black pavement ants. The ants may be observed dragging live or dead cuisine back to their mounds to be surgically dismantled for protein. Since these ants are considered beneficial, management efforts should focus on dissuasion. For example, the pavement ants and field ants loathe thick, high-cut turfgrass. Repeated destruction of the mound ants abode can persuade them to locate elsewhere.
Information from the Ohio State Unibersity Buckeye Yard and Garden On-Line
http://bygl.osu.edu/
Friday, May 22, 2009
Turf - Red Thread
Red thread disease in turf has been found recently. The following is more information.
Red thread has been diagnosed in a mixed turf of bluegrass and perennial ryegrass. The infected patch had a pink cast with red fungal threads easily seen upon close inspection. Although considered a disease of stressed turf, all turf can be infected under these ideal conditions. Red thread only infects the blades causing temporary damage. Infected turf will recover with time. Fungicides applied at the first signs of infection may help reduce damage but treatment is not usually warranted.
Red thread is a foliar disease that usually occurs on taller mown turfgrasses during spring and fall. The disease is often associated with malnourished, low quality, slow growing turf, but the effects of the disease are largely cosmetic. Red thread symptoms create an undesirable appearance, but crowns and roots are not infected, so plants are not killed and turf eventually will recover.
Red thread most commonly affects Kentucky bluegrass, perennial ryegrass, and tall fescue. Outbreaks usually occur in low maintenance turf stands such as residential lawns, golf course oughs, and some low budget athletic fields. Red thread development is most common where turfgrass nutrition is poor and there are other factors that promote slow growing turf.
The most important nonchemical (cultural) control option involves implementing an adequate nitrogen fertility program. A good fertility program implemented over two to three years will drastically reduce further red thread problems. Other cultural practices that promote healthy turf and vigorous growth also help suppress red thread. Outbreaks may be reduced further by avoiding irrigation practices that extend dew periods (such as watering in the late afternoon and early evening).
Photo from the Purdue University fact sheet BP-104-W on red thread disease of turf.
Information from Bob Mulrooney, Extension Plant Pathologist, UD and Purdue University fact sheet BP-104-W by Philip Harmon, Graduate Research Assistant and Richard Latin, Professor of Plant Pathology http://www.ces.purdue.edu/extmedia/BP/BP-104-W.pdf
Red thread has been diagnosed in a mixed turf of bluegrass and perennial ryegrass. The infected patch had a pink cast with red fungal threads easily seen upon close inspection. Although considered a disease of stressed turf, all turf can be infected under these ideal conditions. Red thread only infects the blades causing temporary damage. Infected turf will recover with time. Fungicides applied at the first signs of infection may help reduce damage but treatment is not usually warranted.
Red thread is a foliar disease that usually occurs on taller mown turfgrasses during spring and fall. The disease is often associated with malnourished, low quality, slow growing turf, but the effects of the disease are largely cosmetic. Red thread symptoms create an undesirable appearance, but crowns and roots are not infected, so plants are not killed and turf eventually will recover.
Red thread most commonly affects Kentucky bluegrass, perennial ryegrass, and tall fescue. Outbreaks usually occur in low maintenance turf stands such as residential lawns, golf course oughs, and some low budget athletic fields. Red thread development is most common where turfgrass nutrition is poor and there are other factors that promote slow growing turf.
The most important nonchemical (cultural) control option involves implementing an adequate nitrogen fertility program. A good fertility program implemented over two to three years will drastically reduce further red thread problems. Other cultural practices that promote healthy turf and vigorous growth also help suppress red thread. Outbreaks may be reduced further by avoiding irrigation practices that extend dew periods (such as watering in the late afternoon and early evening).
Photo from the Purdue University fact sheet BP-104-W on red thread disease of turf.Information from Bob Mulrooney, Extension Plant Pathologist, UD and Purdue University fact sheet BP-104-W by Philip Harmon, Graduate Research Assistant and Richard Latin, Professor of Plant Pathology http://www.ces.purdue.edu/extmedia/BP/BP-104-W.pdf
Thursday, April 23, 2009
Turf - Red Thread Disease
The following is information on red thread disease of turfgrasses.
Laetisaria fuciformis, the causal agent of Red Thread, is now infesting susceptible perennial ryegrass and fine fescue turf. Infections are characterized by the appearance of short red threads (1/8” to 1/4” long) emerging from tan-colored leaf blades. Affected patches are typically pink in color and range from 1 to 6 inches in diameter. Kentucky bluegrass and tall fescue may also be affected in the spring. Red thread is typically found on “hungry” (low fertility) turf during cool, wet weather. Well-fertilized turf may also be attacked but to a lesser extent than nitrogen deficient turf. To obtain optimum disease control, maintain adequate fertility levels, keep turf properly irrigated, avoid excessive thatch, and apply Armada, Banner, Bayleton, Chipco 26GT*, Compass, Curalan*, Eagle, Endorse, Headway, Heritage, Insignia, Prostar, Rubigan, Tartan, Trinity or Touche* per manufacturer’s recommendations. (*Not for use on home lawns)
Red thread disease on bluegrass. Photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org.
Information from Bruce B. Clarke, Ph.D., Specialist in Turfgrass Pathology, Rutgers University.
Laetisaria fuciformis, the causal agent of Red Thread, is now infesting susceptible perennial ryegrass and fine fescue turf. Infections are characterized by the appearance of short red threads (1/8” to 1/4” long) emerging from tan-colored leaf blades. Affected patches are typically pink in color and range from 1 to 6 inches in diameter. Kentucky bluegrass and tall fescue may also be affected in the spring. Red thread is typically found on “hungry” (low fertility) turf during cool, wet weather. Well-fertilized turf may also be attacked but to a lesser extent than nitrogen deficient turf. To obtain optimum disease control, maintain adequate fertility levels, keep turf properly irrigated, avoid excessive thatch, and apply Armada, Banner, Bayleton, Chipco 26GT*, Compass, Curalan*, Eagle, Endorse, Headway, Heritage, Insignia, Prostar, Rubigan, Tartan, Trinity or Touche* per manufacturer’s recommendations. (*Not for use on home lawns)
Red thread disease on bluegrass. Photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org.Information from Bruce B. Clarke, Ph.D., Specialist in Turfgrass Pathology, Rutgers University.
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