By Scout Nelson
North Dakota’s weather has created very different conditions across the state this year. In the west, ranchers and farmers welcome timely rains after years of drought. Livestock have more forage, crop yields look strong, and even trees are recovering.
On the other side of the state, however, too much rain has created new challenges. Central and eastern regions are dealing with foliar fungal diseases that are damaging trees and shrubs. Ash anthracnose, apple scab, oak leaf blister, and frogeye leaf spot are some of the problems showing up in large numbers.
Lilacs are suffering the most. A fungal disease called Pseudocercospora has caused widespread defoliation across the region. Many lilacs are nearly bare of leaves, leaving them weak and stressed. Last year, some of these plants bloomed again in the fall, which was beautiful but drained their energy before winter. While many recovered in the spring, repeated defoliation makes it harder for shrubs to survive long term.
Most trees can handle one season of stress, but two or three years in a row can lead to serious decline. That makes management especially important. Experts recommend raking and destroying fallen leaves to reduce the spread of disease. Preventative fungicides may also be applied in spring as new leaves expand, with additional treatments if wet weather continues.
Fertilizer, often thought to be a cure, is not always helpful. While nutrients can support leaf growth, they do not give plants the energy needed for recovery. In some cases, too much fertilizer can attract insect pests.
Categories: North Dakota, Crops, Livestock, Weather