October 10, 2001
Stillwater Gazette
Betsy Halden

Pine needle drop and all about pumpkins

We love to walk in our Lake Elmo neighborhood with our Samoyed, Theodore. The fall leaf color makes the paths and roads appear to wind through a land of gentle beauty. This is probably true with your neighborhood. In addition to the brightly colored leaves, we walk in places through thick carpets of yellow-brown pine needles. Here is an explanation for the heavy needle drop in conifers.

Coniferous trees such as pines, spruces, firs, and cedars normally shed needles in the fall. The older, inner needles turn yellow then straw-colored to brown and drop from the tree. Depending on the tree species, the foliage on a given branch may thin progressively over one to three years. For example, spruce and fir needles also turn yellow and drop with age, but they retain their needles for several years.

On white pines, a more dramatic yellowing of older needles takes place. By November, only one year’s needles may remain attached to the tree. Austrian and Scotch pines usually keep their needles for three years. Some needles turn brown rather than yellow as they age. This is true of arborvitae and cedars. Adverse conditions in the preceding summer or winter may lead to an earlier or more pronounced needle drop in the fall.

In conifers, nutrient deficiencies can also lead to general yellowing and premature senescence of needles. An accurate diagnosis of the plant tissue may help identify the problem. The University of Minnesota Extension Yard & Garden line can help.

Pumpkins!
This is the time of year many of us think about pumpkins and jack-o’-lanterns. Those of us who do not grow our own enjoy selecting plump pumpkins at local garden and produce centers and bringing them home in celebration of fall and harvest. Pumpkins grew originally in South America. The varieties of pumpkins vary in size from 9-65 pounds or more. Shapes vary. The pumpkin rind is smooth and usually lightly furrowed or ribbed.

Pumpkins are grown in the U.S., Great Britain and Europe for human and livestock feed. It takes approximately 100-120 days to raise a mature pumpkin. In Europe the pumpkin is mainly served as a vegetable. In the U.S. it is used in pies and soups.

When they are ripe, pumpkins turn from green to orange. When they are harvested they should be fully ripe with firm rinds, bright orange color, and fairly heavy weight. Pumpkins should be cut from the vine leaving the stem as long as possible. The fruit should be wiped clean of soil.

Pumpkins should be taken out of the field before the temperature drops to freezing. If pumpkins are left outside in temperatures much below 50 degrees F, they may be damaged by chilling injury. If they do spend several days in cold temperatures it is best to leave them outside. They will last longer in the cold than if brought into the warm house where they will deteriorate rapidly.

If the grower has to take in some pumpkins that are not ripe, pumpkins can still turn orange when stored inside. The process can be accelerated by putting the pumpkin in a bag with apples which give off ethylene, a ripening gas. They keep several months at 40 degrees F. Pumpkins keep even longer after curing at 60 to 70 degree F in high humidity for 1 to 2 weeks. Be careful not to bruise the fruit. Bruises will cause the fruit to deteriorate rapidly.

Betsy Halden is a Master Gardener with the University of Minnesota Extension Service. University of Minnesota Extension Service materials were consulted in the preparation of this column. You can reach Betsy Halden at eahalden@comcast.net