The Richmond Register

February 26, 2013

Protect the health of your fruit trees

By Amanda Sears
Extension Agent

RICHMOND — It is never too early to protect the health of your fruit trees.

Proper pruning and spraying can combat diseases such as fireblight.

Fireblight is a bacterium that affects apple and pear trees.

This bacterium enters the tree through the blossoms.

Early symptoms may include a burnt appearance of affected blossoms and twigs. The ends of branches will take on a curve similar to a shepherds crook.

The bacteria may live on the surfaces of branches and in diseased wood.

Prune out and destroy all dead or diseased shoots and limbs while the trees are dormant.

Do not cut the limbs flush with the trunk, instead leave the branch collar. This will allow the tree to heal properly from the cut.

Do not prune your trees once they are actively growing because diseases can be spread on your tools.

If you must cut the tree outside of the dormant season, avoid spreading disease by disinfecting blades of cutting tools between each cut with one of the following: 70 percent alcohol, 10 percent solution of household bleach, Pinesol, or 5 percent Lysol.

Be sure to remove all pruned material from around the trees and destroy it, it could be harboring disease organisms.

With apples and pears, you should consider using fixed copper sprays in late winter or early spring when the trees are still in dormancy. In the past, growers often used copper sulfate to control such problems as fireblight.

However, copper sulfate burns buds on the trees and therefore must be done during dormancy.

Most growers now use fixed copper, which has been made safer with lime.

It is less likely to burn buds and can also be mixed with dormant oil sprays (insecticides), unlike copper sulfate.

It may be difficult to find fixed copper, but ask for products such as Blue Shield 50WP or Kocide. These sprays kill the bacteria on the surface of the wood

The bacteria may linger on in areas that have cankers.

Educational programs of the Cooperative Extension Service serve all people regardless of race, color, age, sex, religion, disability or national origin.

Proper pruning and spraying can combat diseases such as fireblight.

Fireblight is a bacterium that affects apple and pear trees.

This bacterium enters the tree through the blossoms.

Early symptoms may include a burnt appearance of affected blossoms and twigs. The ends of branches will take on a curve similar to a shepherds crook.

The bacteria may live on the surfaces of branches and in diseased wood.

Prune out and destroy all dead or diseased shoots and limbs while the trees are dormant.

Do not cut the limbs flush with the trunk, instead leave the branch collar. This will allow the tree to heal properly from the cut.

Do not prune your trees once they are actively growing because diseases can be spread on your tools.

If you must cut the tree outside of the dormant season, avoid spreading disease by disinfecting blades of cutting tools between each cut with one of the following: 70 percent alcohol, 10 percent solution of household bleach, Pinesol, or 5 percent Lysol.

Be sure to remove all pruned material from around the trees and destroy it, it could be harboring disease organisms.

With apples and pears, you should consider using fixed copper sprays in late winter or early spring when the trees are still in dormancy. In the past, growers often used copper sulfate to control such problems as fireblight.

However, copper sulfate burns buds on the trees and therefore must be done during dormancy.

Most growers now use fixed copper, which has been made safer with lime.

It is less likely to burn buds and can also be mixed with dormant oil sprays (insecticides), unlike copper sulfate.

It may be difficult to find fixed copper, but ask for products such as Blue Shield 50WP or Kocide. These sprays kill the bacteria on the surface of the wood

The bacteria may linger on in areas that have cankers.

Educational programs of the Cooperative Extension Service serve all people regardless of race, color, age, sex, religion, disability or national origin.