Excerpts from Jim Conrad's
Naturalist Newsletter

Pigeonberry, Rouge-Plant, Baby Peppers -- RIVINA HUMILIS

from the December 20, 2009 Newsletter issued from Hacienda Chichen Resort beside Chichén Itzá Ruins, central Yucatán, MÉXICO
PIGEONBERRY

Along trails and at woods edges there's lots of the two- to six-ft-high, herbaceous-looking but woody- based plants bearing racemes of white flowers shown above.

If the plant looks like a diminutive pokeweed it's because usually it's assigned to the Pokeweed Family, the Phytolaccaceae, though some put it into the Petiveria Family, the Petiveriaceae, which I've never heard of. In English it's called Pigeonberry, Rouge-Plant, Baby Peppers and other names. It's RIVINA HUMILIS, and the reason it has English names is that it grows in the US Deep South, as well as the West Indies, and Mexico south into South America. It's a delicate-looking plant but clearly a tough one if it can prosper over such a large distribution.

The flowers, only about 1/8th inch long (4 mm), bear looking at. One with its four swoop-backed sepals, four stamens looking like matchsticks with crooked heads, and the ovary with its slender neck, or style, bent to one side before thrusting the pollen-receiving stigma beyond the clustered anthers is shown below.

flower of Pigeonberry, Rouge-Plant, Baby Peppers -- RIVINA HUMILIS

One wonders why the flower feels the need to bend its style. All Pigeonberry flowers do it, and it seems to be a feature of the whole genus.

As racemes of Pokeweed flowers soon give way to dark purple fruits, Pigeonberry's flowers soon are replaced by glossy, bright red berries, as shown below:

fruits of Pigeonberry, Rouge-Plant, Baby Peppers -- RIVINA HUMILIS

The berries, though very eye-catching with their gaudy redness as you walk along a trail, are small, only about 1/8th inch across (4 mm). Despite one of the plant's names being Baby Peppers, the fruits aren't spicy-hot at all. They taste slightly unpleasant, a little bitter and oily. Birds eat them but not as readily as you'd expect of a fruit so perfectly sized for bird-nibbling and so visible. You see some racemes holding ripe, red fruits for days with no one eating them. Maybe this is explained by a website referring to Pigeonberry as a toxic plant that causes milk taint if cows eat it.

Also I read that juice from the berries once was used as a dye and ink, and that the fruits contain a pigment known as Rivianin or Rivinianin, which is very similar to betanin, the pigment found in beets.

In tropical and subtropical areas Pigeonberry makes a fine groundcover in places too shaded for other plants. In deep shade it simply grows smaller than where it has plenty of sunlight, but it still produces pretty racemes of white flowers followed by crimson berries of questionable edibility.