In June of this year, one of the arboretum's burr oaks was boasting numerous tiny acorns. This was a surprise given the paucity of fruits observed in previous years. Given this strange turn of events, we were curious to see how many acorns would ripen in the fall.
This past week, the burr oak acorns caught our attention again. But the acorns weren't on the tree! Immature acorns of varying sizes started to collect underneath the trees, rather than in the canopy. To make a photographic inspection, we collected a few handfuls of acorns and acorn pieces.
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| These acorn parts were collected in the leaf litter and along the gravel path under the burr oak. Among these immature acorns we have both large and small examples, as well as fragments. What brought about this mess? It looks as though an animal gnawed on a few of the acorns, breaking them up into tiny pieces. Were the acorns still on the tree at the time, or had they already fallen to the ground? Was this the work of a squirrel, a posum, or some other beast? |
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| While the exterior of the cap is rough and dull-colored, the interior is smooth and shiny. This dissection also shows off the characteristic burr oak fringe. |
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| Varying sizes of immature acorns were found. Were these knocked loose? Or did the tree simply release them to conserve resources? |
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| A few large acorns were found. They measured more than an inch across, but still have an immature look. |
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| At this stage of development, these burr oak fruits might be mistaken for the fruits of the overcup oak (Quercus lyrata), as the cap nearly encloses the whole acorn. However, at maturity, the burr oak acorn is clearly visible. For comparative photos, check out this old post. |
