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To maintain a healthy lawn requires knowledge of common lawn diseases. And that can invade it. These diseases are mostly caused by fungi. Its introduced to the lawn by agents such as wind and animals. The fungi can also be found in the soil in their dormant state. Become activated once the right conditions and host plant are introduced. A host plant is a plant susceptible to an attack by a specific fungus.
Reasons of Lawn Diseases
Conditions favoring fungal growth include high humidity, poor watering practices. And inadequate air circulation in your lawn. Fungi are very stubborn and require hard work to eliminate. Hence one should work on prevention rather than cure. Let us look at 10 common lawn diseases and the organic methods of controlling them.
#01: Powdery Mildew Lawn Disease and Treatment
This appears as a white powdery splotch on leaves and stems of plants. It is usually noticed when it appears on the upper surface of the leaves. It will also affect the plant stems, flowers, buds and the fruit. When it covers the leaf, it impairs photosynthesis resulting in stunted plant growth. Repetitive infections tend to weaken the plant, but it is rarely fatal. An infected bud will not mature, and this results in loss of fruits.
There are several types of powdery mildew fungi which infect different types of plants. These fungi are host specific. And that is fungi infecting one type of plant species cannot infect a different plant species. The fungi go into a state of dormancy in winter then start reproducing in warm conditions.
These fungi are carried to the plants by wind. And water or by sticking to insect bodies and deposited on your lawn. These fungi never stop reproducing. Until the infected leaves disposed by burning. High humidity, plant crowding and poor air circulation encourage the growth and spread of this disease.
Powdery Mildew Treatment
There are many ways to treat this disease from your lawn. But here you can learn the organic way to control this disease. Powdery mildew can be controlled by:
- Improving air circulation in your lawn by pruning and thinning out. This will help dry out the excess moisture. It will ensure good air flow which picks up moisture and help in evaporation. To achieve this you can thin your lawn.
- Destroying all infected plants. Spores from infected plants can be transferred to healthy plants. Mow Your lawn to burn all of them.
- Avoid watering your lawn from above. Drip irrigation is recommended. Watering from above will lead to accumulation of water on the leaves. To form a breeding ground of fungi. Ensure you water close to the ground.
- Plant a powdery mildew resistant variety. A resistant variety will withstand attacks from powdery mildew.
#02: Brown Patch Lawn Disease and Treatment
Brown patch disease appears as circular patches of brownish. to yellow grass ranging from six inches to several feet in diameter. The cause is a species of fungi called Rhizoctonia. It affects grass that thrives well in moderate spring to fall temperatures. These grasses include perennial ryegrass, tall fescues and the bent grasses. It is particularly harmful to ryegrass and tall fescue. Brown patch mostly affects the blades of grass hence is a foliar disease. Brown/tan lesions appear on the infected grass blades.
The affected grass usually remains upright. And may recover at the middle of the patch giving it a ringed look. Brown patch usually occurs during periods of prolonged heat and high humidity. These fungi rest during the winter waiting for a rise in temperatures. And humidity to start reproduction.
They are capable of surviving in the soil waiting for a suitable host plant to be introduced. The excessive nitrogen content in the grass, poor air circulation, poor soil drainage and poor irrigation methods accelerate brown patch development.
Brown Patch Treatment
Brown Patch disease is an another one of common lawn diseases. It can be controlled by below organic ways:
- Providing air circulation by dethatching. Flowing air will pick up excess moisture which is then evaporated ensuring no moisture is left for sporulation.
- Use of proper watering practices. Water in the morning to ensure plants absorb the required moisture. The excess moisture will be evaporated as the weather heats up. Water close to the ground to prevent water getting on the plant leaves.
- Proper soil maintenance to improve on drainage. Prepare the soil well to enable water penetration to the soil. This will avoid water from becoming stagnant and creating a breeding ground for fungi.
#03: Red Thread Lawn Disease and Treatment
This is a turf grass disease that is usually caused by low levels of nitrogen. It usually affects bermuda grasses, bent grasses, blue grasses, fescues and ryegrass. Red thread can be detected as a red to pink thread or webbing seen on the grass. Also it is usually a harmless disease and indicates the need to fertilize your lawn.
High humidity, low levels of nitrogen and temperatures ranging from 65 to 75 degrees Fahrenheit are the main factors that favor red thread disease. Just like the brown patch disease, it affects grass that thrives well in moderate spring to fall temperatures.
Red Thread Treatment
Red thread lawn disease can be controlled by increasing nitrogen levels. You can do the read thread treatment in organic way. Here are few ways to treat red thread. It can be controlled by:
- Water the lawn deep early in the morning. This will allow the grass to absorb the necessary moisture and ensure excess water is evaporated as the weather heats up.
- Maintain a soil ph of 6.5-7.0. An acidic or alkaline soil would lead to the death of microorganisms in the soil. These microorganisms’ break down organic compounds and mineral nutrients required for the grass to thrive.
- Ensuring adequate levels of nitrogen is maintained. Nitrogen helps in the growth of grass and ensures the grass recovers in case of injury.
#04: Snow Mold Lawn Disease and Treatment
Snow mold disease appears as patches of discolored grass that appear early in the spring. All grasses include annual bluegrass, bluegrasses, fescues, ryegrasses and zoysiagrasses.These patches could be straw colored or matted with a white coating. This usually appears after thawing of snow and will thrive if the weather is cool and damp. It is caused by gray snow mold and pink snow mold.
These fungi survive the hot summer conditions and become active in the winter. They germinate and produce mycelium beneath the snow that infects the plants. These fungi remain active in the spring if the weather conditions remain cool and damp. And the infected areas will usually dry up as the weather warms up. As long as it snows in the winter, these snow mold conditions will remain from one season to the next.
Snow Mold Treatment
If your lawn affected by snow mold, it gone everything. Because of color. You can’t see any green in your lawn and that is really painful. So you need snow mold disease treatment. But we don’t want to do it by using any chemical which is very bad for our environment. So here are few organic treatments for your lawn. Yes, snow mold can be controlled by these ways:
- Mow the grass shorter. This will prevent moisture from getting trapped in the grass. Tall grass prevents sun rays from reaching the ground leading to trapping of excess water.
- Collect leaves to avoid moisture getting trapped. Having a large surface area, leaves will trap excess water preventing evaporation. Rake fallen leaves to avoid this.
- Spreading out snow to help it thaw. Densely packed snow takes longer to thaw. This is because of poor heat distribution. Spread it evenly to aid in its thawing.
- Avoid nitrogen fertilizer in the fall. While nitrogen is essential for the growth of grass, it leads to the development of a thick thatch which would trap moisture. Nitrogen has also been found to predispose grass to disease attack.
- Cutting up any thatch that is more than a half inch thick. This will also help in preventing moisture from getting trapped in the grass.
#05: Fairy Ring Lawn Disease and Treatment
This disease is caused by certain types of fungi and affects all lawn grasses. It usually appears as a ring of toadstool especially in an area of high moisture rings of deep green and lush grass or an area of dead brown grass between areas of lush grass. The causative fungi form threads in the soil. These threads are densely packed and deeply rooted. This tight packing thread will prevent uptake of nutrients and water by the grass thus killing it.
These threads can be so devastating as to cause to the annihilation of the grass cover leading to soil patches. However, they are mainly located in a particular area hence do not cause widespread damage. These threads are very hard to remove ad care must be exercised when uprooting them.
Fairy Ring Treatment
There is an easy way to treat fairy ring disease in organic way. What is this? See here: fairy ring disease can be controlled by:
- Uprooting the toadstools and burning them so as to prevent spores from being spread. Spores found in the toadstools can be transferred to healthy grass by wind or animals. Uproot and burn these toadstools to contain the disease.
- Mowing the affected area independently of the rest of the lawn. Make sure you collect the entire grass clippings and dispose of them by burning. This will lower the chance of spores being transferred to healthy areas.
#06: Dollar Spot Lawn Disease and Treatment
This disease is caused by a fungus of the Lanzia and Moellerodiscus species and usually attacks bermudagrasses, zoysiagrass, ryegrass, fescues and annual bluegrass. It appears as small circular spots, white or tan in color, ranging from one to five inches in diameter. These spots may merge to form large irregular areas. Leaves of the affected plants often appear as water soaked to brown in color and exhibit a reddish band across the leaf. In the morning it will appear as a fine white mycelium covering the leaves.
Symptoms of dollar sign usually occur from early to late summer. This disease is favored by moderate temperatures ranging from sixty to eighty degrees Fahrenheit, excess moisture and thick thatch. The causative fungus is spread by wind, water or carried by feet.
Dollar Spot Treatment
Dollar spot disease can be controlled in these organic ways:
- Reducing thatch. A thick thatch will create a breeding ground for fungi by trapping moisture.
- Appropriate irrigation to a depth of four to six inches. This will ensure grass gets the moisture it requires while avoiding moisture from getting on the leaves where it would offer a suitable area for sporulation.
- Maintaining air flow. Well spaced grass will allow air to pick up excess water hence assisting in its evaporation.
- Top dressing with compost to suppress disease. This will ensure that spread of the spores by wind or animals is controlled.
#07: Fusarium Blight Lawn Disease and Treatment
Also known as necrotic ring spot, this is a devastating disease that is usually noticed during prolonged hot and dry conditions of summer. It usually appears as small patches of dead grass. Grass may grow again in the middle of the patch giving it a frog eye appearance. This disease usually affects the Kentucky blue grass. The basal area of the dead stems has a reddish rot that is hard and tough. During these hot and dry summer conditions, the areas affected by this disease will turn from green to straw in color.
This disease is caused by a fungus which produces spores when daytime temperatures reach seventy degrees Fahrenheit. As the temperatures reach seventy-five to ninety, coupled with high humidity, spore production increases and this kill the infected area quickly. Thick thatch and drought– stressed areas also favor this disease.
Fusarium Blight Treatment
If your lawn is affected by fusarium blight, don’t worry. You can treat this disease in easy way by organic method. Well, here is it: It can be controlled by:
- Water your lawn appropriately. Watering early in the morning allows grass to absorb necessary moisture for growth and ensures the sun dries up the excess.
- Mowing to the recommended height. Short grass favors excess water evaporation and prevents crowding.
- Thinning the thatch. Thick thatch means more trapped moisture and high humidity in the grass accelerating sporulation.
- Mixing a 20% mixture of perennial ryegrass when planting bluegrass. The ryegrass will survive in drought conditions and shelter the bluegrass from the harsh sun which would cause the bluegrass to dry up. The ryegrass will also absorb water from the soil keeping the soil conducive for bluegrass to thrive.
#08: Pythium Blight Lawn Disease and Treatment
Also known as grease spot, this disease affects all kinds of grass but mostly devastating to bent grass and ryegrass. When the weather conditions are favorable, it can wipe out the whole turf grass. It appears as small circular spots of two to six inches in diameter that run together. Diseased patches fade in color. The leaf blades wither rapidly and turn reddish brown. They then wither, stick together and appear greasy. And the roots may appear brown, and when the humidity is high, fungal mycelium appears.
The causative fungi may survive for long in the soil. At the right conditions, it produces spores which will infect turf grass. The conditions that favor this disease include low spots that remain wet and warm temperatures ranging from eighty to ninety-five degrees Fahrenheit. Under these conditions, Pythium blight can spread very rapidly. It also develops faster in high nitrogen levels than in lower ones.
Pythium Blight Treatment
If you lawn is covered by bent grass, you have to chance in pythium blight disease of your lawn. But you can control by organic way. Yes, this disease can be controlled by:
- Reducing shade to allow any accumulated moisture to dry up. Damp conditions are a key factor for fungi reproduction.
- Improving air circulation in the soil and ensuring proper water drainage. This greatly improves on the evaporation of excess water.
- Water at the recommended length of time. This will not only allow grass to take up required moisture but will also ensure that excess water dries up when temperatures increase during the day.
- Allow the grass to dry before mowing. Mowing wet grass traps moisture which is required for spore formation.
- Do not apply heavy doses of nitrogen especially when the weather conditions are hot and humid. This is because nitrogen helps in the growth of grass leading to the formation of a thick thatch which will trap moisture.
#09: Rhizoctonia Large Patch Disease and Treatment
Mainly affects Bermuda grass, Kikuyu grass, Zoysiagrass and St Augustine grass. It usually occurs as brown patches caused by Rhizoctonia solain. It occurs during periods of warm and humid weather conditions. Initially, it appears as small brown patches that grow in diameter as the infestation progresses. The middle may regenerate to form rings of brown grass. The leave and covering become water soaked wither out and turn brown and die. In mild infestations, the roots avoid being affected and later regenerate.
The causative fungus forms fine fungal threads in the soil and if not properly controlled may spring back each fall at the same place. The fungus survives high temperatures and becomes active early in the fall. It goes into a state of dormancy during winter and resumes its destruction in spring. It spreads in all directions killing leaves and shoots. This disease is favored by wet soil conditions, excess thatch and cool temperatures of between sixty and seventy degrees Fahrenheit.
And if your lawn is covered by bermuda grass, be aware from Rhizoctonia disease of your lawn. But if you are already in this disease with your lawn, no problem. It can be controlled by these organic ways:
- Reducing shade to allow moisture to dry up. This will remove trapped moisture which fungi require to reproduce.
- Improve soil aeration and drainage of water. Water build up in the lawn will speed up sporulation hence the soil should be well tilled.
- Maintain thatch of less than half an inch. Air flow will help remove trapped moisture required by fungi to reproduce.
- Irrigate properly to a depth of four to six inches. This not only allows water uptake by the grass but also prevent a buildup of excess water.
- Avoid excess nitrogen use in fall. This is because nitrogen helps in the growth of grass leading to the formation of a thick thatch which will trap moisture.
#10: Summer Patch Lawn Disease and Treatment
This disease is also known as Poa patch. It occurs in bluegrasses and fescues. It appears initially as yellow to brown colored patches ranging from six inches to three feet in diameter. These patches may join up to form large patches. Healthy grass can be found at the center of the patch hence resulting in the formation of rings of dead grass. And the roots and stolon will have dark fungal hyphae on them.
These later escalate to vascular discoloration and cortical rot. The causative fungus colonizes the grass roots, and favorable conditions accelerate its attack on the roots. This disease usually occurs during high temperatures followed by wet conditions.
Conditions favoring summer patch infestation include excessive moisture, mowing the grass very low and temperatures of above eighty-five degrees Fahrenheit. Summer patch can be confused with necrotic ring spot hence the need for careful diagnosis by a qualified person.
Summer Patch Treatment
The Summer patch disease’s another name is Poa patch. But don’t worry if your lawn is affected with this disease. Summer patch can be treated easily if you want. But how? Well, see here, it can be controlled by these organic ways:
- Aerating the soil and improving the drainage. Well drained soil prevents stagnation of water which would offer a breeding ground for fungi.
- Mowing to the proper grass height and high temperatures favor the development of this disease. Cutting your lawn’s grass too low. So will cause an increase in temperatures encouraging sporulation.
- Maintaining the soil pH at seven or below. So this will ensure microorganisms required for nutrient breakdown thrives. These nutrients help the grass to grow.
- Controlling thatching and keep your thatch thin to prevent trapping of moisture.
- Irrigating early in the morning. So this will help with evaporation of excess moisture as the weather warms up. And this organic way work very fine.
Final Thoughts on Common Lawn Diseases
In conclusion we have looked at ten common lawn diseases. So that are likely to affect your lawn and their organic methods of control. Also Organic methods are beneficial in that harmful. Yes, if harmful chemicals find in fungicides may destroy your lawn. So these chemicals are carried by rainwater. And introduced to other plants and marine life. When we consume these products, we introduce these chemicals into our body system causing health complications. So be careful before use any chemicals in your lawn. Another way is take care your lawn before affected your lawn.