Mast, which many wildlife species depend on in winter, is abundant this year, according to field surveys conducted by the Virginia Department of Game and Inland Fisheries (VDGIF) and the Virginia Department of Forestry (VDOF).
“Seems like 2018 was a solid year for just about anything — granted everything did not hit everywhere, nevertheless, a good year all-around for hard and soft mast,” Gary Norman, Leader of VDGIF’s Forest Game Bird Project, wrote in an email exchange I had with him regarding this year’s annual survey. Norman co-coordinates the department’s mast survey with district wildlife biologist Katie Martin and coordinates the joint VDGIF-VDOF survey and an eight-state regional survey.
“Mast” refers to the fruits of the forest consumed by wildlife — “hard mast” for nuts, including acorns, and “soft mast” for soft fruits, such as grapes and berries. Hard mast provides protein, fat and energy that can be essential for surviving winter, when weather can be harsh and other food sources become scarce.
In monitoring hard mast, both surveys focus on acorns. Produced by oak trees, these nuts constitute the most important hard mast for Virginia wildlife because of their nutritional content and abundance. In a good year, oaks can produce more than a quarter ton of acorns per acre, covering the forest floor and outproducing other nut trees.
Ninety species of Virginia’s native animals feed on acorns, according to the VDGIF, and most of these species also feed on a variety of other nuts. The importance of hard mast to game — deer, black bear, wild turkey, ruffed grouse and quail — is the main reason this department monitors the production of hard mast.
North American oak species are taxonomically divided into two groups: white oak (Leucobalanus) and red oak (Erythrobalanus). The easiest way to tell the two groups apart in the field is by their leaves: those in the white-oak group have round lobes and those in the red-oak group have pointed lobes. Within each group are species by the same name as the group, which can be confusing. For these surveys, two species in the white-oak group are monitored — white oak (Quercus alba) and chestnut oak (Q. montana) — and one in the red-oak group, northern red oak (Q. rubra).
Acorns and other wild nut crops have also been important food sources for humans since they first arrived in Virginia. The magnificent American chestnut (Castanea dentata) dominated the eastern forests at that time and was as important as oaks in producing hard mast. When a blight all but wiped out the chestnut in the first half of the 20th century, the oaks ascended to the throne. Now they, too are declining for a host of reasons, mostly attributable to humans. Among the two oak groups, acorns from white oaks are generally preferred by animal and human consumers because they are “sweeter” (less astringent) than those from red oaks.
Both Virginia mast surveys are conducted on public lands. For its survey, VDGIF combines Virginia’s Blue Ridge, Ridge and Valley and Appalachian Plateau physiographic provinces into one region, “Mountain,” and also conducts surveys in the Piedmont and Coastal Plain provinces. These survey regions are further divided latitudinally into nine subregions, with Rappahannock and Culpeper counties falling within the North Piedmont subregion. Although these artificial boundaries are useful for collecting and reporting data, it’s good to remember that nature doesn’t draw such clear lines.
For its mast survey, VDGIF staff inspect 40 white oak and 40 red oak trees along a route that traverses high and low elevations, and east and west aspects, Norman explained in our email exchange. The 80 trees are marked so they can be used from year to year. The staff inspect the crown and estimate the percent with acorns. The abundance is graded numerically as 1-3 — “poor,” “moderate” or “good.” As Norman acknowledged, “The limitation of this survey is that most of our field staff are in western VA, where our public lands are.”
This year the North Piedmont’s crop of white-oak acorns was “perhaps the best in the state, exceeding its long-term average,” Norman and Martin reported in a press release. The South Piedmont had a “fair” crop, as did the Central Mountain region, which is usually less abundant. The Central Piedmont’s crop was low enough to be considered a “failure,” which also applies to the other two Mountain subregions. And while the red-oak acorn crop in the North Piedmont exceeded its long-term average, the crop was “poor” throughout the entire Mountain Region and the South Piedmont and “fair” in the Central Piedmont.
Nut production from hickory and walnut trees is also included in the DOF surveys. This year, overall, both beat their long-term averages, according to Norman. When I compared personal observations on these crops with Joe Rossetti, the VDOF senior forester for our area, we both found these nuts to be scarce this year. This is not surprising, considering mast abundance can vary considerably by location.
The joint survey also delivered good news on mast crops, both hard and soft (see my Nov. 28 column for the soft-mast results). According to a Nov. 19 memo Norman wrote to VDOF and other organizations managing the public lands surveyed, overall “production of white oak and chestnut oak acorns declined from the bumper ratings in 2017, but were still rated moderate in abundance.” They “exceeded” their long-term averages, while red-oak acorn production was “below average.” In our area, white-oak production was “good,” while red-oak production was “poor.”
The joint survey also includes beech-nut production, which this year was also good, equaling its long-term average. Anecdotally, Rossetti reported seeing “more beech nuts this year than I ever have before,” adding that “some people even gathered beech seeds to give to our nursery!”
In our email exchange, Norman wrote that he hopes to combine the results of the two Virginia mast surveys “eventually” using a special statistical procedure, which would provide “lots of benefits.” In the meantime, wildlife depending on mast this winter should be happy with this year’s production.
© 2018 Pam Owen