Authored by Jennifer Nicotero in Gardening
Published on 01-01-2009
It can be disheartening to see your fruit tree suddenly take on a sickly look and produce poor fruit. Unfortunately, disease in fruit trees happens frequently and it is sometimes due to neglect. Although some diseases can be controlled, others can take hold and kill your fruit tree quickly. There are preventative measures you can take to ensure a disease-free growing season for your fruit trees.
One common disease for tree growers to contend with is apple scab. Apple scab is a fungal disease that will disfigure the apple fruit with brown patches. The leaves will also develop black and brown spots. To combat this fungus and keep it under control, spray your trees with a lime-sulfur spray prior to the buds opening in the spring season. After the leaves are fully open and the weather is wet and warmer, spray twice a week. Stop spraying around mid-summer and apple scab should be under controlled for the rest of the growing season.
Black knot is a fungal disease that attacks the branches of many cherry trees. It appears as knotty, black bulges. Prune these branches if you see them in late winter. In the spring, spray lime-sulfur when the buds appear to swell and repeat in seven days.
Another fungal disease of the cherry tree is cherry leaf spot. This disease forms tiny purple-black and red spots on the leaves. As this disease progresses the spots drop out of the leaf, while the leaf itself remains intact on the tree. You can control cherry leaf spot with a sulfur spray every ten to twenty days or so. If this disease is left untreated, it is likely it will eventually kill the tree.
The peach tree has a number of fungal diseases that can attack it. The best care you can give peach trees are to give them preventative sprays. Give the peach tree a sulfur spray at blooming time, and again when the fruit begins to color. This spraying helps to control brown rot, peach scab and bacterial leaf spot. Repeat this spray every ten days to a few weeks until harvest time.
Fire blight is a common bacterial disease of the pear tree. The twigs and leaves on the tree will look scorched and burnt. The leaves will also curl up and turn black. Fire blight can eventually kill a tree if left untreated. To combat fire blight, spray your pear tree with copper or streptomycin prior to the flowers opening and every four days while they bloom. After bloom, it is wise to spray every six or seven days until the fruit has taken form. You will also want to prune out any infected shoots caused by fire blight by cutting approximately eight inches below any sign of disease. Destroy and burn the diseased branches or shoots. A pear tree is another fruit tree that would benefit greatly from a dormant oil spray in late winter or early spring.
Although these are the most common diseases your fruit trees may encounter, there are many other diseases as well. The best protocol to take in protecting your fruit trees from disease is by taking proactive measures before hand. We often take for granted that our trees will do well year after year. However, it doesn’t take long for a fungus or disease to destroy your fruit tree when unattended.