Masting Trees

A friend told me last week that he suspected we’d have a rough winter, “because the oaks in my yard are dropping a huge amount of acorns.” The notion that the size of nut/seed production in the fall correlates with the mildness or harshness of the following winter has been around for centuries. I got the idea from my dad, who got the idea from his dad, who got the idea . . . and so on.

Such country lore has always been fascinating to me, and since I enjoy being outdoors and like to collect wild nuts and seeds, I’ve noted the prodigious production of black walnuts this year. Because farmers and denizens of small towns in the American Midwest and Northeast often planted black walnut trees both for their nutmeats and for their wood (black walnut being a prime wood for furniture), walnut trees are abundant around us, thanks in part to squirrels, which transport the walnuts hither and yon for eating, storing, and forgetting.

Red oak acorns

Edible seeds such as acorns, hickory nuts, walnuts, and beechnuts are often referred to as mast. When these trees produce a crop larger than typical, foresters say they are “masting.” Masting among such trees happens every few years. The effect of it is to ensure that not all the seeds will be consumed by squirrels and other seed/nut eaters and allow the tree to reproduce. In the lean years, nut predators thin out, and while they’re gone, the trees take notice and drop a ton of seeds to ensure germination. So suggest the botanists


But when you read research conclusions about masting, you discover that there seem to be many mysteries about the occurrence. For instance, oak trees within a radius of some 350 miles often mast at the same time—as if they all got the Manager’s memo! And certainly around here this year the oaks, walnuts, and beeches got the message. Masting also doesn’t seem to depend on weather factors like the amount of sunshine or rain over a season, nor does it seem to be related to pollination or to soil and atmospheric chemistry. There appears to be some relationship between masting and more global climate factors, such as those that create the el nino and la nina effects. But there seem to be no firm conclusions about it.

I confess to getting a little bit of perverse pleasure when “nature” throws naturalists a mean curveball like tree masting. Scientific researchers can get pretty cocky when they feel they’ve discovered the cause for this or that natural process. We humans all need regular reminders that we really don’t have all the answers—probably not even most of the answers. Sometimes I think trees are laughing up their leaves.

Black walnuts

This year, a few million more walnuts around the Midwest are going to have a better chance to germinate. There are not enough squirrels to collect them all—a fact that’s made it easier for me to harvest a couple hundred of the tasty nuts from a single tree (leaving far more on the ground than what I had in my buckets)! The expression “a hard nut to crack” certainly must have come from those who harvested walnuts. Shucking, drying, and cracking walnuts is hard and messy work, but the flavor reward is worth the effort.

An extra privilege of my collecting walnuts this year was the location of the tree. It was in Woodlawn Cemetery in southeast Grand Rapids. This is the “garden of remembrance” where the bodies of Dr. M. R. De Haan, the founder of Radio Bible Class (RBC Ministries), his wife, and Richard De Haan, Dr. De Haan’s son and past president of RBC, are buried. Since my mom and dad came to the Lord through the ministry of “Doc” De Haan, I like to

stop by his gravestone to get a refill of gratitude for him and for the ministry I now serve. On his memorial marker is the two-word phrase he used at the end of all broadcasts that came into our home every Sunday throughout my childhood and youth: “Perhaps Today.”

See you outdoors!


[NOTE: This was written in the fall of 2011.  The ensuing winter was the mildest on record in Michigan!  So the country lore about masting being an predictor of the severity of winter may be far from accurate.]