Damping-Off Disease

Discuss how to and whether you should renovate your lawn
Post Reply
User avatar
andy10917
Posts: 29165
Joined: February 23rd, 2009, 10:48 pm
Location: NY (Lower Hudson Valley)
Grass Type: Emblem KBG (Front); Blueberry KBG Monostand (Back)
Lawn Size: 1 acre-2 acre
Level: Advanced

Damping-Off Disease

Post by andy10917 » September 6th, 2018, 9:36 am

One of the biggest early scourges of renovations is Damping-Off Disease, which is tricky for several reasons.

First, if you applied Milorganite, Bay State or any organic fertilizer, it's not easy to see the difference between harmless Mycellium decomposing the material and Damping-Off mycellium. The thing to look for is WHERE the cottony-white mycellium are - harmless mycellium will be on the soil, while Damping-Off will be on the actual grass or forming a cottony web-like mess between the blades.

Damping-Off is also tough to treat often because there are several fungi that can cause it. As fungicides are mostly not very broad-spectrum, picking the wrong one may be both costly and ineffective. Pythium needs a film of water to spread, and Rhizoctonia solani spreads by hyphae . Both are attracted to grass seedlings by the products the seedlings put into the soil, and they topple the seedling almost at soil level and then eat the dead matter.

Once it gets going, Damping-Off will cause seedling death in expanding circular or irregular patches that stop expanding for no apparent reason. Pythium will often spread in the direction water flows.

In addition to synthetic fungicides, the biologics like Mycostop and Actinovate work pretty well, but like Serenade are better at planting/seeding time than after an infection is established.

Overly Heavily-seeded lawns and seeding blankets can raise the incidence of Damping-Off as they reduce air-flow. Overwatering the soil is also a major contributor.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest