Monthly Archives: May 2018
Ascochyta Leaf Blight
Lawn disease can affect any lawn at any time; regardless of having a professional lawn care company or, if you are a do-it-yourself, lawn diseases can and will happen. A disease in a lawn can occur when a host (grass), a pathogen (fungi) and ideal environmental conditions are present. These conditions include but are not limited to day time and night time air temperatures, moisture, rain, sunlight, lack of sunlight, and improper watering and mowing. Once these factors, although different for each disease, are met the disease can start up. If the environmental conditions remain favorable a disease can persist for extended periods of time. The longer a disease remains active the more damage it can potentially do to the turf. Fungi can remain dormant in the soil for years until the correct environmental conditions that favor a specific disease before an outbreak occurs. Lawn diseases can be distributed by wind, rain, foot traffic, lawn mowing equipment, etc. Common for the late spring, ascochyta leaf blight can greatly impact the look of the lawn.
What is Ascochyta Leaf Blight
Ascochyta leaf blight is a common foliar disease that occurs in the late spring to early summer. This disease is more common during hot, dry periods and followed by cool and rainy conditions. The symptoms of ascochyta leaf blight appear as large irregular patches of turf that rapidly turn a straw-color and appear to be dead. From a distance the straw-colored areas resemble drought stress. The infected leaf blades appear to be sucked in from the tip down. While this disease looks very serious when outbreaks are widespread, it is actually quite harmless. This disease will not cause any permanent injury to the lawn. This disease will spread very fast by foot traffic, rain, and lawn mowing. Often times, mowing machines pick up the fungus and spreads the disease throughout the lawn, creating a stripe like pattern of the disease in the lawn. Cultural practices are the only way to help get rid of the disease.
This picture illustrates how ascochyta leaf blight can be spread from a mower.
What kind of grass does it effect?
Kentucky bluegrass is the most susceptible to ascochyta leaf blight; however tall fescue and perennial ryegrass types are also vulnerable to the lawn disease.
Cultural management
Watering properly is key to controlling ascochyta leaf blight. Avoid light, frequent irrigation in the early morning while surface moisture is present. Deep, infrequent watering that occurs between 12 am – 6 am and we recommend to water 1 – 1 ½ hours per zone every third or fourth day is best. For more information about watering your lawn, check out our blog.
Proper mowing also helps. Do not mow in the morning when the lawn is wet from the dew or last night’s scheduled watering. This will spread the disease further. Mow the lawn in the afternoon when the surface moisture has evaporated. Keep the lawn height at 3 – 3 ½ inches in length. Mow off 1/3 off the grass plant at a time.
Fertilize regularly to help stimulate growth of the grass. The faster the grass is growing the faster the disease will get grown out of the lawn on its own.
Core Aerate the lawn regularly in the early fall to help reduce thatch (where disease harbors) soil compaction. This will also help to create a stronger root system and grass plants.
Unfortunately, fungicide treatments are not available for this particular disease.
Conclusion
It is important to remember that ascochyta blight will not kill your lawn. It simply needs to grow out on its own with a little help from you, the homeowner. If the conditions remain favorable this type of disease can persist for weeks. After all cultural practices have been done, the only other thing you can do is be patient. Give it time, your lawn will be okay.
If you have any questions about ascochyta leaf blight and you are in our service area, please give our office a call at 908-281-7888 or request an estimate.
Red Thread Lawn Disease
A closeup of red thread lawn disease.
Lawn diseases are frustrating for every homeowner that desires to maintain the picture-perfect lawn and landscape. Unfortunately, the warmer temperatures of the spring-time that we all love; along with frequent rainy periods, creates the perfect storm of environmental conditions to be just right for fungus to grow in the lawn. A frequent spring-time lawn disease observed in many lawns is Red Thread Disease.
What is Red Thread Disease?
Red Thread Disease is caused by the fungus Laetisaria fuciformis, and is most notable during the early spring months. The first observable symptoms of red thread lawn disease are tan-to-red thread like growths called sclerotia, often seen in patches of 4 to 6 inches in diameter. Two environmental conditions that are key components to the fungus growing are high levels of humidity and temperatures between 60 to 75; making the spring time optimal for the disease to spread. The sclerotia strands can protrude upward from the blade tip of the grass, making them noticeable among other patches of disease free, green grass.
What kind of grass does it effect?
Although all varieties of turf grass are susceptible to red thread lawn disease; perennial ryegrass has been found to be the most susceptible, and fine fescues are also especially susceptible.
Cultural Management
Although the disease is unsightly, red thread lawn disease does not cause permanent injury to the grass. The key to controlling red thread lawn disease culturally is to promote turf growth. Maintaining adequate nitrogen and good soil moisture are the two most important factors when dealing with a red thread outbreak. This will not only help to grow out the disease but, also creates a stronger healthier lawn overall. As the new growth occurs, the disease portions are cut away, leaving the healthy turf underneath exposed.
When red thread lawn disease has been a persistent issue, checking the soil pH level and maintaining a reading between 6.3 and 6.7 may help in reducing the issue. Also, the sclerotia survives in the thatch layer of the lawn. Heavy thatch build up and soil compaction can be reduced by core aeration, and we recommend this procedure is performed biennially in the late summer or early fall.
Additionally, it is important to practice watering techniques that will not overwater your lawn since the disease thrives under moist conditions. We recommend watering between midnight to 6 am and for those that have underground irrigation systems, run each zone for 1 hour twice a week. For traditional hose end sprinklers, run the sprinkler for 4 hours per area of coverage twice a week. For more information about watering your lawn, check out our blog.
If optimal weather conditions persist for this fungus, it will continue to spread more rapidly than the grass can grow it off. In this case, it may take several weeks to over a month for complete recovery of the turf.
Treatment for Red Thread lawn disease
While this fungus will not kill the lawn, it can be frustrating for homeowners to deal with this eye sore for weeks while it grows out. If red thread lawn disease is severe, a fungicide treatment can be applied to the lawn. Post application, the disease will not be able to actively spread for three to four weeks. This allows the lawn time to grow out the infected grass blades more quickly than the disease can spread, and the fungus is gradually cut away with regular mowing.
Conclusion
Red thread lawn disease is common; luckily it does not cause permanent damage on your lawn. Most red thread outbreaks can be kept under control through sound cultural practice, and the lawn can soon return to the green state it was prior. For especially bad cases, fungicide treatment is available to control the red thread lawn disease. If you have any questions about treating red thread lawn disease and you are in our service area, please give our office a call at 908-281-7888 or request an estimate.
Eastern Tent Caterpillar Moths
About Tent Caterpillars
The eastern tent caterpillar moth is a native North American pest, that can regularly be found throughout New Jersey. Tent caterpillar nests are a common sight on cherry, apple and crabapple trees in the late spring and early summer months. These unsightly silken webs are built in the crotches of the tree limbs and can become quite large based on the number of caterpillars on the tree. During the day you may see these nests filled with hundreds of caterpillars. Eastern tent caterpillar moth populations fluctuate from year to year with large outbreaks occurring every eight to ten years. During years with high populations the eastern tent caterpillar moth can also be found on plum, pear, maple and hawthorn trees.
The eastern tent caterpillar moth overwinters on the tree as an egg, usually in a mass of 150-400 eggs. These egg masses are covered with a shiny black material the helps protect the eggs during the winter months. Once spring arrives the larvae hatch, this is normally around the same time cherry tree buds open and the trees begin to produce leaves. As the larvae crawl, they produce a silken string which is the beginning of their nest.
What Tent Caterpillars Feed On
The caterpillars feed for 4 to 6 weeks on the foliage of the host tree and grow to approximately 2 to 2 ½ inches in length. Feeding generally occurs during the day time if temperatures allow. Most feeding will occur within 3 feet of each tent caterpillar nest, so it is common to see multiple nests per host tree. During the night, or in the rain the caterpillars will stay inside the nest for protection from the elements. As they grow so will the size of the nest. The eastern tent caterpillar moth can defoliate a tree when populations are high, and some tree species may be killed if the tree does not have enough time to grow a new set of leaves for food production and storage prior to the winter. Any level of feeding and leaf loss weakens the host tree. In home landscapes the nests can become an eyesore, especially as defoliation occurs and they become more visible.
Mature eastern tent caterpillar moths will leave the host tree and search for a suitable, protected location to spin their cocoon and pupate. It is during this wandering phase that they become a nuisance and can be a mess when found on driveways, patios and walkways. The caterpillars are no longer feeding at this time, so no further damage will be caused to surrounding trees. Once a favorable location has been found the caterpillar will spin a white or yellowish cocoon. Once inside the cocoon the caterpillar transforms into a pupa and remains in the cocoon for approximately 3 weeks. Once fully mature, the eastern tent caterpillar moth emerges from the cocoon. Adult eastern tent caterpillar moths are reddish-brown in color and have a wingspan of about one inch. Male and female eastern tent caterpillar moths mate and the female will begin to lay eggs on small branches. These eggs will hatch in the spring of the following year. We see one generation of eastern tent caterpillar moths in New Jersey per year.
If you have experienced tent caterpillar moth damage on your trees, we recommend learning more about Deep Root Fertilization to promote tree recovery.
Treatment
There are a wide range of treatment options for eastern tent caterpillar moths that range from removal to chemical control. Beneficial insects, birds and toads feed on the eastern tent caterpillar moth. Beneficial wasps parasitize eggs, larvae and pupae reducing that year’s eastern tent caterpillar moth population. Early control is essential in minimizing damage to the host tree. Pruning of small twigs and branches that contain egg masses can be done in the winter prior to the eggs hatching in the spring. Small tent caterpillar nests may be removed and destroyed in the spring. Tent caterpillar removal is best when the nest is small, prior to feeding damage. The tent caterpillar nest should be destroyed or disposed of offsite. Removing the nest from the host tree and leaving it on site will allow the caterpillars to migrate to another host tree.
The application of registered insecticides by a licensed company is also a tent caterpillar treatment option. Tent caterpillar treatments must be applied to the host tree once the tent caterpillar nests are visible. They are protected while inside the nest, so it is important the tent caterpillar treatment be applied to the branches and leaves of the host tree as well as the tent caterpillar nest. As the tent caterpillars venture outside of the nest to feed they ingest the tent caterpillar treatment and are controlled. It is important to only use a licensed pesticide applicator for the treatment of eastern tent caterpillar moths. The timing for tent caterpillar treatment is critical as the application is only effective up until the wandering phase.
Conclusion
If you have a history of eastern tent caterpillar moth activity on your property contact your tree care company to discuss tent caterpillar treatment options and timing for your area. If you are in our service area and have any questions about this pest, feel free to contact our office at 908-281-7888 or request an estimate.
