Ever wonder which oak trees produce the most acorns where you hunt? Well, the key to improving acorn production in your oak stands is first and foremost identifying the best producers. Unfortunately, not all large, healthy-looking oaks produce impressive crops of mast on a consistent schedule. In this article, I’ll explain a visual survey technique that is simple to conduct and effective at identifying good acorn producers. Once identified, you can encourage the best, most consistent acorn producers in the stand to become outstanding producers with a few timber-management techniques.
Identifying Oaks with Superior Acorn Production
In this survey, you will calculate the average number of acorns produced by each tree by literally counting the number of acorns within 24 inches of the tips of a few healthy branches. You then rank acorn production as either: excellent, good, fair or poor (see the table). Trees ranked as excellent or good producers are marked as the best producers in the stand for the year of the survey. The survey is conducted once each year and should be conducted for three years (not necessarily consecutive) prior to any timber harvest that ultimately will thin the oak stand. A three-year survey is best because it enables you to identify between 85 and 100 percent of the best acorn producers in your stand. If you can’t devote the time to a three-year survey, a one- or two-year survey is better than nothing. However, surveys conducted for less than three years can miss one quarter to one half of the excellent producers in the stand. Remember, the best producers may not produce acorns every year nor may they be the best producers every year they produce a crop. Thus the need for a three-year survey.
Conducting the Survey
The best time to conduct the survey is between August 10 and September 5. During this time, acorns are developed enough to been seen from the ground, and acorn predators (birds, insects, etc.) won’t have eaten your entire crop. Surveys don’t need to be conducted in consecutive years, but at least one survey should occur during an abundant crop year. An abundant crop year is one where nearly all trees produce at least some acorns and most trees have clusters of acorns distributed throughout their crowns. Ideally, the survey should be conducted by the same person(s) each year to allow for a consistent survey between years.
To conduct the survey, all you will need is the ranking procedure, a good pair of binoculars and a way to mark your trees. I’ve found that a bright-colored spray paint, found in any hardware store, is a cheap, convenient way for temporarily marking trees. The paint is quick to use, easy to see, it can’t break like plastic flagging, and it won’t damage your trees. Also, paint usually fades from view within three years, so it will last long enough for your survey but won’t be permanent.
Start your survey at the first oak you come to in the stand. Identify if it is in the white oak or red oak family. Next, look at the top third of the tree and use your binoculars to estimate the average number of acorns growing within 24 inches of each branch tip. In the white oak family (see photos in Gallery below), mature acorns are located near the tips of the current year’s growth, so white oak acorns are best viewed from a location where you can see the outside edges of the tree crown. In the red oak family mature acorns are located on last year’s growth and appear to be clustered tightly against the twigs, so they are best viewed from directly below the tree crown.
Next, use the ranking procedure mentioned earlier to determine if acorn production for that tree is excellent, good, fair or poor. If you determine it is excellent or good, mark the tree with the spray paint. If it is fair or poor, the tree remains unmarked. Move on to the next tree, and continue the survey. Once you get going, the process of counting acorns and marking trees will take about 45 to 60 seconds per tree.
When you mark an excellent or good tree, I suggest using a dot of paint placed about chest high on the tree. I mark each tree with a total of four dots, one dot on each “side” of the tree. This allows me to see marked trees regardless of the angle I approach them. I make the paint dots just large enough to see from a distance. To help keep track of which trees you have surveyed in the stand, you can place a small dot of paint near ground level on fair- and poor-quality trees; any tree without marks at chest height is a candidate for removal from the stand.
Conduct the survey the exact same way each year, ranking acorn production of all oaks in the stand and marking excellent and good producers for that year. Use a different color paint for each year of the survey to keep track of which trees were consistent producers and which year each tree produced a good acorn crop. For example, over a three year survey the trees that have three marks in your oak stand should be your best, most consistent producers.
Once you have identified the best acorn producers in the stand, it is time to conduct a timber harvest to improve acorn production. The efforts you have taken with your acorn survey, combined with the appropriate timber management steps, will encourage consistent, abundant acorn crops from your oak stands. I'll follow up with a second article offering guidance on timber thinning to improve acorn production, but in the meantime you can get busy with your acorn survey.
The information for this article was originally published in QDMA's Quality Whitetails magazine, authored by Matthew Tarr – University of New Hampshire Cooperative Extension Wildlife Specialist – and is shared here as a sample of the information QDMA members receive. To start receiving Quality Whitetails, join QDMA today.