Today, one of the largest remaining plots of American chestnut trees in New Hampshire is located at the UNH Kingman Research Farm. But the spread of the chestnut blight fungus ( Cryphonectria parasitica) in the early part of the 20th century, it took less than four decades for American chestnuts to become nearly extinct, and with it, the disappearance of robust lumber market the species supported. Colloquially referred to as the “Redwoods of the East,” American chestnuts ( Castanea dentata) grew wide and tall-as high as 100 feet and a dozen feet in diameter-and ranged from the Lower South up to Maine. If you could travel back 120 years and walk through a New Hampshire forest, you’d notice something quite different: the American chestnut being a core part of New England woodlands. Chestnut nuts are still used though, especially in cooking they are imported largely from Europe and come from European and Asian chestnut species.Within 50 years, the pathogen had so impacted the American chestnut that it mostly didn't grow past shrub or sapling stage. Chestnut blight ( Cryphonectria parasitica) was introduced at the start of the 20th century.Chestnuts would be transported between urban areas by railroad car and sold-either fresh or roasted-in major cities. American chestnut nuts were a significant source of food for wild animals, and also for agricultural animals.Later on, it was used for railroad ties and telephone poles. It was used for everything from log cabin foundations to flooring to caskets. During Colonial America, the American chestnut was highly valued for its resistance to rot.It was among the largest and tallest trees in the region. There were once nearly four billion American chestnut ( Castanea dentata) trees in the Eastern United States.Infected flowers taken by Srdjan Acimovic, Arborjet Inc. Main photo taken by Srdjan Acimovic, Arborjet Inc. When early spring dead wood removal is combined with annual treatments of Arbor-OTC, canopy loss will be tremendously reduced. Trees that have adequate soil moisture and warm daytime temperatures will distribute Arbor-OTC upward in the tree within 7-10 days. The earlier in the bud break the injections are conducted, the better fire blight reduction is achieved. As late spring and summer temperatures begin to climb, the bacteria will go dormant when water in the soil is scarce and when temperatures are around 85-90☏.Īdditional treatment with Arbor-OTC at petal fall will continue to benefit the health of the tree until daytime temperatures reach this level.

This shelf-stable water-soluble powder comes in two sizes and does not require refrigeration.Įarly spring injections of Arbor-OTC® just as buds break is the most optimum time to treat susceptible trees. However, if the weather conditions are most favorable for disease progression and spreading, the whole canopy can be severely affected with a burned appearance thus the name Fire Blight.Īrbor-OTC is a systemic, water soluble, injectable antibiotic for the annual suppression of bacterial diseases in non-food bearing trees and palms. By further spreading of the bacterium with rain splashes and insects to other flowers and shoots, symptoms will often appear scattered throughout the canopy. The bacterium moves into the wood of twigs and lateral branches, which express black cankers and can turn completely black. The first sign of a fire blight infection is early death of flowers and then green shoots immediately adjacent to the flower petiole. Trees infected with the fire blight bacterium Erwinia amylovora often have extensive limb cankers and dieback with a characteristic “Shepherd’s Crook” appearance at the tips of the shoots. Flower infections can be introduced by bees and other insects from infected wood cankers that ooze bacterial substance in the spring. This disease is most often found in pear, apple, loquat and crabapple trees and has become a nuisance to homeowners and commercial landscape managers. Spongy Moth, formerly known as “Gypsy Moth”įire blight is the most damaging bacterial disease that affects shrubs and trees in the Rosaceous family during warm spring weather combined with rains or heavy dews.

Fire blight on trees