The cool moist spring has been great for extending the bloom
period on azaleas and dogwoods; however, turf fungus seems to be thriving in
these conditions.
Large Patch or Brown Patch fungus loves these weather conditions.
Temperatures in the high 50’s to low 60’s and moisture make conditions real
favorable for Large Patch or Brown Patch fungus. We have had plenty of these conditions
making the fungus environment perfect for the spread of this disease.
Since it is very difficult to control night time
temperatures, you can put your efforts into doing other cultural things to help
minimize the disease. Large Patch or Brown Patch fungus likes wet, heavy
thatch, improper nutrition, and/or compacted soils. Culturally you need to manage your irrigation
system, raise any low areas, and correct drainage problems. Reducing thatch, maintaining proper fertility
levels, and aerating to alleviate compaction, will also help control Large
Patch or Brown Patch fungus.
Certain organic products have shown to increase
microorganisms in the soil that compete with plant pathogenic fungus in the
soil. At Possum’s we get good feedback from Nature’s Blend, SeaHume, Crab
Shell, Corn Gluten, Cotton Burr Compost, and some of the Roots products. These
products are not fungicides; however, people that use them report back to us
that they notice less fungus in the yards that they apply these products.
Since the grass is coming out of dormancy so slow, a systemic
control product like Cleary’s 3336 and Disarm might be a good idea to get you
through the next month or so as long as conditions are favorable for the
disease.
Being a soil borne disease, you know that it will reoccur in
the same areas year after year. If the
base of a leaf blade with Large Patch is moved from one part of the yard to
another (lawn mower), this can begin a new infection area; however, these are
not spores flying through the air. As a
soil borne fungus, if you map the areas that you have the disease, you can
concentrate your control efforts (dollars) into a smaller area, putting less
control products into the environment.
If your yard is 5,000 sq ft usually you might have a few infected areas
which might total approx. 500 ft.
Instead of buying control products to treat 5,000 sq ft, you can
concentrate your efforts into the 500 ft (i.e. 10% of your total yard). If Large Patch was an air borne fungus with
spores, you would have had to treat the entire yard because air borne fungus
spreads a lot quicker than soil borne fungus.
