Tag Archives: fat deer

Why Are There Many More Acorns Some Years Than Others?

Every several years at Medicine Spirit Ranch we receive an unbelievable number of acorns. My oak filled yard becomes thoroughly covered by acorns. The periodicity of the big acorn crop occurs every two to five years, and I assumed it had something to do with the weather with wet Springs and hot dry Summers. Being a curious type, I went online only to find that increased amounts of rain and heat units do not adequately explain the periodic acorn bonanzas. What I also learned was that the cycles of none or few acorns punctuated by heavy acorn crops has been well recognized by botanists and the years of acorn boom times go by the name, Mast Years.

Our ranch has many Live Oak trees, red oaks as well as some Post Oaks. Across the world many different varieties of oak exist but all oaks produce acorns. The acorns are of course necessary for new trees to develop. The acorns also provide feed for squirrels, deer, feral hogs, turkeys, raccoons, mice, Blue Jays, Woodpeckers, quail,some types of ducks, and in some parts of the United States bears. We have even found our young Border collie, Duke, eating acorns. Acorns are highly nutritious.

The question arises as to why Mast Years exist at all. As it turns out science has not fully explained this curious event. As noted above weather and environmental factors are insufficient to explain it. Some scientists have speculated that an unknown environmental trigger may exist or that some type of chemical signaling may occur among the oak trees. Science up till now has simply been unable to adequately explain the mast year phenomenon.

One personally satisfying theory for Mast Years is that these cycles have a evolutionary benefit for oak tree development through “predator satiation.” What this means is that the lean years will not support as many animals who graze on acorns, thus thinning their numbers. Then a boom year of acorns occurs, such that many acorns go uneaten by the depleted number of foragers, increasing the chances of developing into new oak trees. Are Oak trees this “smart?” Well, it does make a certain amount of sense.

As a result of our current Mast Year, we can expect large herds of well nourished deer. Unfortunately, mast years also encourage the survival of more invasive and destructive species such as feral hogs. These hogs have become an increasing problem on our ranch and growing to 300-400 pounds and reproducing large litters twice as year, can out compete the cows and sheep for food and water. The feral hogs also destroy fences and can menace humans and livestock.

In a larger view, the interaction between an acorn bonanza and the fauna that feed on them establishes a symbiotic relationship that benefits all. Without having the opportunity to live at Medicine Spirit Ranch, I would not have ever realized this unusual integration of fauna and flora.