If you have nut trees in your yard, you have probably noticed that we have had a tremendous crop this year. The acorns have been dropping on my roof and car for weeks. Earlier it was the pignut hickory, and the hulls from the beech tree (the squirrels eat virtually every beech seed, so it’s mostly hulls). The falling nuts are like organic hail, right down to the dents in the car roof. And it’s noisy; the other night I took advantage of my wife being out of town to binge watch The Walking Dead. As a warm front blew through, the acorns rained to the deck, bouncing up to hit the door and windows. Very unnerving.
Recently, I’ve seen deer under my oak trees in the early morning. They may be coming to eat the acorns. Wildlife ecologists call acorns and other fallen nuts “mast” which I guess comes from the same Latin root as masticate (“to chew”).
I think next year we might have a bumper crop of deer. November is peak deer mating, or rutting, season. Does, which may mate in their first year if well-fed, produce variable numbers of fawns. When there is abundant food (e.g., lots of acorns), does often have twins, and occasionally three or four. Love among the acorns.
The preferred fall-season acorns come from white oaks, because they have fewer tannins than red oaks and black oaks. (Tannins are the bitter chemical compounds that might make you pucker up when you drink “heavy” red wines, or, I don’t know, chew on an acorn.) As tannins slowly disappear over the winter, bitter acorns become more palatable. I believe that one of the reasons squirrels hide acorns for later use is because they actually taste better in the spring. Luckily, I have black oaks so I don’t have as many deer as I might if I had white oaks.
Some years there is a heavy crop of acorns, others light. Apparently there are many factors influencing acorn set, including the species of oak, the number of flowers on the tree (which is determined by weather factors in the previous year or two), and the amount and timing of rainfall, which washes the pollen out of the air and reduces pollination. Oaks are wind-pollinated, so when the weather folks are talking about the tree pollen count and it’s high, it probably includes oak pollen.
This acorn feast sort of bridges the summer season, when deer eat primarily herbaceous browse (leaves, seedlings, your garden…) and the winter, when they eat primarily twigs, buds, and evergreen foliage. They eat 3% of their body weight per day, so for a 100 pound doe, that’s three pounds of acorns, or hostas, or azaleas, or whatever is on the menu.
Since deer are creatures of habit, now (late fall) is the time to apply repellants to your yews, azaleas, and whatever other shrubs may have been browsed in past winters. If you can get deer to avoid your shrubs now, they may leave you alone for the winter.
Reapply repellants to new growth as perennials and shrubs leaf out in spring. This is to reduce summer browsing by nudging them to browse on the next block. They frequent the same areas on a regular basis, so the idea is to get them in the habit of going somewhere besides your garden. Once they have you on the route, the repellants are much less effective.
Without looking at the acorns or the browsing deer, the White Oak group is easy to distinguish from the Red Oak group by their leaves: White Oaks and their relatives have blunt edges on the leaves; Red Oaks and their relatives (including the Black Oak) have pointy edges.
by Larry Hurley, Behnke horticulturist