Excerpts from Jim Conrad's
Naturalist Newsletter

from the December 15, 2008 Newsletter issued from Mayan Beach Garden Inn 20 kms north of Mahahual, Quintana Roo, México

One of the most common and conspicuous shrubs or small trees here on the dry sand rise between the sea and the mangroves -- thus in competition with real-estate-minded humans -- is the species shownbelow:


That's Seagrapes, COCCOLOBA UVIFERA, easy to recognize by its large, roundish, leathery leaves often ornamented with red veins and splotches, as shown below:

Seagrapes, COCCOLOBA UVIFERA, stipular sheath

The last picture also shows a detail that helps us recognize which plant family Seagrapes belongs to. Notice the red, collar-like "sheath" surrounding the stem at the base of the leaf's petiole (See the little wolf spider hiding in the sheath?). This sheath is a special kind of stipule, which itself is a special kind of modified leaf.

In most plants with stipules there's an inconspicuous stipule on each side of the petiole's attachment to the stem. Stipules protect tender emerging shoots and flowers as they expand from their buds, and the stipules typically shrivel and fall away once the parts they're protecting are fully developed. In the Seagrapes' family, however, stipules extend all the way around the stem forming this cuplike sheath.

When you see stipular sheathes like this the first family to come to mind should be the Buckwheat Family, the Polygonaceae. In North America the most commonly encountered members of the Buckwheat Family are the smartweeds or knotweeds, often seen in weedy and/or wet places. If you're familiar with the way small smartweed flowers are arranged on spikes you won't be surprised to see what Seagrapes flowers look like below:

Seagrapes, COCCOLOBA UVIFERA, flower

Actually, that spike has lost nearly all its flowers; it's a bit late in the season to see Seagrapes flowers here. However there's at least one tiny white blossom to be seen in the picture, against the cloud's base.

Up north, Seagrapes produce drooping, grapelike clusters in late summer, each fruit being about 2 cm in diameter (0.8 inch). The fruits contain pits and are enough like grapes for jam to be made of them or eaten straight from the tree. Seagrapes don't grow too far north, however, because they're not frost resistant. They are indeed tolerant of shade, however, are highly tolerant of salt, and ecologically are very important for stabilizing beaches.

from the June 12, 2011 Newsletter issued from Mayan Beach Garden Inn 20 kms north of Mahahual, Quintana Roo, México

Now at least some of our Sea-grape shrubs are heavy with grapes, as seen below:

Seagrapes, COCCOLOBA UVIFERA, immature fruits

Those mothball-size "grapes" are still a little immature, even though you can see that many already have disappeared from their slender, drooping rachises. My Maya friend Martín explained what's going on:

"It's the chachalacas," he said. "They come every morning to eat the grapes, even before they're mature and juicy When they're ripe, they're yellowish to rosy."

I'd like to find some ripe sea-grapes because I read that they taste good, are tart to sweet, and can be eaten raw or made into jelly or wine. However, I've looked for some all week and so far the chachalacas are winning.

Most of the insides of the grapelike fruits are occupied by a single hard seed and inside that seed you can see something special: The embryos inside most seeds are curled, but Sea-grape embryos are straight. You can see one looking like an egg on a golf tee below:

Seagrape, COCCOLOBA UVIFERA, fruit cross section showing straight embryo

Evolutionary taxonomists usually regard straight embryos as a more primitive trait than curved ones.

from the September 25, 2011 Newsletter issued from Mayan Beach Garden Inn 20 kms north of Mahahual, Quintana Roo, México

Last June I wrote that Sea-grape fruits found in the area "are still a little immature" and suggested that the Chachalacas might eat them before I could get a chance to taste one. To my surprise, all during summer the Chachalacas ate very few and the fruits themselves only recently began reaching maturity. You can see a handful of ripe ones, one partially eaten, even at this date more green than the yellow or brown I've been looking for, below:


That picture also shows the single, hard seed found inside each fruit. The fruits have fuzzy skins, like peaches. The ripe fruits even smell and taste a tiny bit like peaches, but really they have their own taste, which is pleasant enough and nicely sweet. They also taste salty, but I can't say whether the saltiness is in the flesh itself or the salt-spray-exposed, fuzzy skin.

I'm surprised that the Chachalacas haven't harvested them all. In fact, the vast majority of ripe fruits appear to have fallen to the ground where they emit a powerful but not-unpleasant odor of past-ripe fruits that can be smelled a fair distance away.

I read that sea-grapes contain a lot of pectin, and as such are ideal for making jams and jellies. I'll bet they would also brew a tasty homemade wine.

In fact, Marcia has posted a recipe for "Sea Grape Vinaigrette" and "Sea Grape Jelly" down the page at http://www.mayanbeachgarden.com/trees.htm.