ERI Management Programming Tool
ERI pathogens, while not being strong and aggressive, are very persistent and can accumulate within turfgrass root zones.
As a result, once you have an ERI disease it will always be there to some extent just waiting for the appropriate conditions to present itself. The reason for their persistent nature is that ERI diseases are saprophytes which means they don’t require living tissue to survive. They can remain in dead decaying plant matter in the thatch and/or soil waiting patiently until soil temperatures become favourable for growth and development. Symptom expression tends to occur when turf is stressed and/or in soils where the population and diversity of soil biology is low.
The Living Turf Technical Sales Representatives have access to a programming tool to help customers with ERI management and disease control. The ERI diseases covered by the tool are Take-All Patch, Spring Dead Spot and Take-All Root Rot (also known as Couch Decline). The tool is based on documented soil temperatures where these diseases become active and uses a range of soil temperatures to highlight when the activity period for the particular ERI disease is initiated and again when it concludes.
When the disease first becomes active, turf managers should then plan and commence spraying for preventative control. We know these diseases go through dormancy periods based on soil temperatures and once the optimal temperatures are hit, the disease will activate and commence growth and development. It’s not efficient to treat while the disease is still dormant as the disease needs to be active to take up the fungicide.
It is also important to get in early before the disease gets going, so as to limit its concentration within the root zone. The disease is often active and doing damage well before you start to see symptoms which is why soil temperature is a critical indicator. The treatment window is based on the accepted soil temperatures at which the various ERI pathogens become active. Many turf diseases lie within the ERI family however they are vastly different in symptom development and temperatures at which they cause infection. The customised plan will use the closest weather station temperature data to build a relevant management plan for each individual customer.
Treatment requires addressing both cultural practices and fungicide programming on a preventative basis. The timing of applications is critical to achieving success. Soil temperatures are the basis around which the program is developed noting ERI species have different activation temperatures.
High water volumes with soil wetting agent use are essential for incorporation of products into the root zone target area. In addition, cultural management practices such as hollow tyning have been shown to be effective in reducing disease pressure. Minimising turf stress by maintaining ideal moisture and nutrition is advantageous, while also considering other stress contributors such as nematodes and/or mites. It is also important to note that a soil pH above 7 encourages ERI activity, as well as reduces nutrient availability, especially manganese which is important when adjusting pH.
If you would like a customised plan for ERI this season, talk with your Living Turf Technical Sales Representative.