by guest blogger Mary Concklin, Montgomery County Extension Educator.
We have had many droughts off and on over the past decade. The resultant lack of water places plants under stress as well as weakens them. Plants need water to remain turgid and to deliver nutrients. In addition, plants give off moisture on hot days. If water is not replaced, foliage will begin to droop. As drought continues day after day, the damage gets worse.
This year’s drought, occasionally interrupted by a burst of 2 to 5 inches of rain all at once, has certainly wreaked havoc with our plants. With the rare rains we received, water available to plants improved. But in many of our heavy clay soil areas, large amounts of rainfall either runs off with no benefit to the plants or drains very slowly, creating additional stress on our plants by reducing available oxygen to the roots.
One question that comes up just about every year is about needles dropping off pine trees. Pine trees will shed their older needles in the fall as a natural process. They retain the newer needles on the outer portions of the branches. Take a walk in the woods and look on the ground at the terrific mulch made by those shed needles. As they break down, pine needles add organic material to the woodland floor, making it rich with nutrients, worms and other ‘good guy’ soil organisms. So don’t panic when your pine trees begin to lose older needles this fall. The picture shows normal needle drop.
On the other hand, if you notice that newer needles are turning brown and shedding, there is cause for concern. This is an indication the tree is under stress. Drought damage is one of the first things to come to mind if the damage is showing up on the top of the tree and outer edges of branches on both new and old needles,. This type of damage is an indication the roots have been compromised and will not be able to supply water and nutrients to the entire tree. Trees under drought stress are also weaker and less able to fight off insects and diseases. A dying or weakened tree may also be suffering from multiple problems that have been compounded by the drought.
Depending on the extent of the damage, some trees will recover if rain arrives before a large amount of the root system is compromised. If you have questions about what is normal and what isn’t, please call the local Cooperative Extension office in your county. The Montgomery County Cooperative Extension phone number is 610-489-4315.
Do you have a gardening question? In Delaware County, call our Master Gardeners hortline at 610-690-2671 on Tuesdays and Thursdays from 9 AM-12 NOON.
UPCOMING MASTER GARDENERS EVENTS
October 13, 2007: Scarecrow Making
Our annual scarecrow making workshop is a fun family event that is enjoyed by kids of all ages. You bring the clothes, a hat and a pillowcase--we supply the rest.
Registration required for all events (except plant sale). Please call 610-690-2655 for more information or visit our website
