Grow Your Own

Acorns: The Grain That Grows on Trees

Once you've gathered (and sampled!) acorn harvests for a season or two, you might want to plant a food tree in your own yard. By propagating local stock, you'll be able to grow varieties that are well suited to your soil and climate and that may be difficult to purchase.

The first step in planting an oak is to selectlarge, well-formed, healthy acorns from yourfavorite parent tree. Experience in gathering the nuts for eating will help you in thisrespect, as you'll be able to recognize a suitable seed simply by its sheen, color, and feel.Discard any acorns that sport worm holesor are discolored, and remove the caps fromgood nuts soon after you harvest them.

ACORN STORAGE

Fall is the preferred time for planting acorns, as many cold-climate oaks require a stratification period— that is, the nuts must remain at temperatures just above freezing for at least six weeks, and perhaps as long as 20 weeks, in order for the nuts to germinate. However, if you intend to store the seeds for planting at a later date, you can stratify them yourself: Set the kernels in a moist planting medium such as sand, peat moss, vermiculite, or sawdust and place them in cold storage. The acornsofthe white oaks are generally viable for a month or two after ripening, while thoseofthe black oaks are viable for six months or more. Drying the acorns to 60%oftheir initial fresh weight and then keeping them in cold storage (35-40°F) can lengthen the viabilityofwhite oak acorns to about eight months, and similar treatment might further extend the viabilityofblack oak acorns, as well.

PLANTING

Once you've collected your acorns, or received a supplyofnuts from oneofthe firms listed in the accompanying editor's note, you'll need to decide on a propagation method.

Chances are that your acorn cache will be limited, so you'll probably want to grow seedlings in seedbeds, flats, or containers before setting them out in their permanent location. You can even germinate the acorns before planting them in their "nursery" area. To do so , place the nuts about 1 " deep in a plas tic bag filled with moist, sterilized potting medium and store the package at 50-75°F. The acorns should sprout in a few weeks. When the sprouting root is 2-3° long, transfer the tiny tree to a deeper container or seedbed.

Seedbeds. Planting acorns in seedbeds is quite easy, especially if the timingofthe seedlings' growth allows them to be transplanted directly into their permanent ground. This propagation method is not recommended for evergreen oaks, but it works fine for deciduous species.