Diseases On Apple Trees
Apples are delicious fruit for everybody and you are surely to get high yield in the harvest season. However, apple trees will be susceptible to many diseases which may seriously weaken the health of the tree and cause the reduced fruit yield. Most of these diseases are caused by fungus and some of these diseases can be avoided by some simple procedures and protections.
Apple scab is one of the most dangerous diseases infecting some kinds of apple trees. Trees are easily infected during the spring when the weather is getting warmer and there are more rainy days. The main cause of this disease is the Venturia inqequalis fungus. It is dormant in winter days and will be spread by winds during spring and wet days. This fungus will infect the apple tree leaves and cause small lesions on the underside of leaves. Gradually, both sides of the leaves will be covered with lesions and those leaves will fall off with the time passing on. This can seriously weaken the overall health of the apple tree. To avoid this disease, you can choose some apple species which can effectively resist apple scab naturally like Enterprise, Pristine and Williams Pride apples. Since this disease is spread by air, it is not easy to control when it becomes prevalent. So, it is recommended that you should avoid planting those species which are easily infected like Red Delicious, Cortland and McIntosh.
Black rot is another common disease which will infect apple trees. It is caused by Botryosphaeria obtuse and the symptom will be the brown spots on the skin of the fruits. The spots will spread quickly and turn black eventually, resulting in the rot of fruits. Also, the brown spots may appear on the leaves as well. The disease spread to trunks will cause cankers which may result in the death of the tree. If this disease is discovered, you should prune the infected branches as quick as possible and burn those branches instantly to avoid the spread of the disease. Some fungicide can also be sprayed into the tree to get it under control.
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