It’s hard to believe that December is almost here.
The good news in the deer woods is that acorns are still on the ground right now in Northeast Georgia. Deer and deer hunters appreciate this because the animals are fat and healthy and in the middle of a strong rutting season, and then face a long winter. The bad news is that many of the nuts you see on the ground are rotten inside, damaged by weevils, birds, squirrels and weather and consequently passed over by deer whose keen sense of smell can detect the rot inside.
It is much harder for people to evaluate the soundness of acorns. Some have a tiny hole where a female weevil bored through the hull and deposited eggs that hatched into worms (larvae) that feed on the nut inside.
Damaged acorns will float in water, sound acorns sink.
Finally, a small pair of pliers can be used to crush the hull and see for yourself once and for all whether the nut is still good or not. Do this on five or 10 nuts under one tree in midday or afternoon to determine if any sound acorns are still left, and deer are still visiting that tree.
This late in November many white oaks are finished dropping all their nuts for this fall, and the rotten leftovers tell the story.
This fall has been a very good one for white oaks and very lean and spotty for the red oaks.
This can be good news for deer hunters if they can find the remaining productive white oaks or an isolated red oak still dropping nuts as the red oak group drops later than the white oak group.
There are at least 54 species native to the U.S. and they are widely distributed over Northeast Georgia and most of the country.
They thrive at different altitudes and in many different soil types. White oak group species in this part of the state include white, chestnut and post oaks. Red oak species include northern red, southern red, scarlet, black, blackjack and water oaks. All are valuable to wildlife.
Acorns rate a position at the top of the wildlife food list with usage by over 100 species of animals including deer, wild turkey, bears, squirrels, raccoons and many more mammals and birds. White-tailed deer use of acorns has been reported as high as 52 percent of the diet in Texas and up to 50 percent in Missouri and Alabama. Acorns contain a relatively low protein level (6 percent) but are high in fat and carbohydrates at maturity in the fall when deer and other critters need fat to over-winter in a healthy condition.
Acorns have been repeatedly tied to deer abundance, reproduction, buck harvest numbers, body weight, antler development and even over-winter survival. Deer populations exposed to acorn failure followed by a harsh winter are subject to mortality in the Northeast Georgia Mountains and significant loss of weight in Hall County.
One study in North Carolina showed average production of well-developed acorns ranged from 6,600 per acre per year to 94,600 per acre per year. The quality of acorns is as important as the quantity produced. On the average, only two-of-three acorns were fully developed. Of these, the number of sound and undamaged acorns varied from 11 percent to 73 percent. Production of sound acorns on Ã-acre plots ranged from 0 to 145,400 acres. Acorns were damaged by insects (mostly weevils), birds and squirrels, and were imperfectly developed, deformed or aborted. Late spring frosts, poor bloom, and lack of pollination are other important factors affecting the size of the acorn crop each year.
Major differences between the white and red oak groups are that the white oak group blooms and produces a mature acorn in the same year while red oaks bloom and produce a mature acorn in the second year.
The white oak group has rounded leaf margins (lobes) contrasted to pointed lobes with a bristle on the tips of red oak leaves. There are other important differences too numerous to detail here. Due to lower tannic acid, white oak acorns are generally more preferred by deer and other wildlife than red oaks. Sawtooth oak (non-native) is a notable exception to this, reported to be equal to white oak in palatability. This difference in palatability among groups can be very important to deer hunters trying to pinpoint deer movements this month.
The importance of oak species diversity is unmistakable since red and white oaks (probably due to the one year difference in time to maturity) rarely fail in the same year. Consequently, the two groups often buffer each other year after year, preventing a total failure of both groups in the same year. This is important because of the wildly fluctuating nature of acorn production. Deer managers manage oak stands for large crown diameter and air movement around crowns. Peak production age for oaks is usually 50-100 years of age. They select cut to release oaks from surrounding competition such as hickory, white pine, gums, poplar or maple.
Finally, while not proven by research, fertilization of individual trees may help increase acorn production. A complete fertilizer (such as 10-10-10) broadcast underneath mature oaks evenly out to the dripline at the rate of one pound per inch of diameter at breast height (dbh) in the month of March may increase acorn production. Individual oaks located around lawns, pastures, croplands, and other fertilized areas have long been noted for heavier, more consistent acorn production, although other factors (such as insects or air circulation around crowns) may also be involved.
Though inconsistent and unpredictable, acorns make up a very important component of the fall and winter diet of deer and 100 other wildlife species especially where diversity of oak species among both white and red oak groups is high. Although white oaks as a whole are more palatable to deer, red oaks are more consistent producers in the long run.
Kent Kammermeyer is a certified wildlife biologist. His column appears monthly.