You Are Here: Management Updates 2000 Archive January 2, 2000

Date: January 2, 2000
Category: Diseases
Subject: PCNB Phytotoxicity Problems

Phytotoxicity is a common effect following use of PCNB products (such as Turfcide, Defend, etc.), especially on bentgrass. It is more pronounced when the chemical is applied at full rates. It causes a browning of the leaf tips that may look like leaf spot or other disease problem. Close observation, however, will determine that there is usually a sharp line between the browned leaf tip and healthy green tissue below. Also, unlike a typical disease, the effects are usually very uniform across the treated areas.

The unusually warm weather seems to be causing more of a reaction than usual this year or it may be that we can just see the effects more clearly because there is no snow. The good news is that the problem is not a serious threat to the health of the plant. The browned tips will be removed with the first mowing in the spring.

- Submitted by: Dr. Gail Schumann