Behria tenuiflora

Leo A. Martin
Tue, 04 Oct 2011 15:41:18 PDT
I was intrigued by the discussion and looked the plant up on the Wiki.
I've never seen it in habitat but I've been in areas in the Baja Cape that
look like the photos.

The climate in southern Baja California is unusual, so it might be good to
review it.

Temperatures are high all year, very high in the summer. Even at 2200m
altitude it will be above 90F in the daytime during summer, and not much
cooler in the winter. Nights at altitude will be cooler than near sea
level, but there's a reason resorts didn't take off in the Cape until air
conditioning was invented.

In the winter there may be several days of overcast weather with coolish
rain, but it's not nearly as cold as southern California in the USA. Since
the plant grows over a wide altitude that means temperature isn't that
important; the plant is hot all year.

Precipitation is completely irregular in the Cape region, which receives
somewhat more rain than the area to the north, because the tropical storms
tend to track more to the south. Rain arrives at any time of year with big
storms that dump a lot of water in a relatively localized area. Gentle
winter rains are rare but possible. Many Baja plants are adapted to grow
at any time of year when water is available.

The photo shows a plant growing in a dry watercourse. Such soil is loose
and composed of varying sizes of gravel and sand. After a good rain
upstream, there will be surface water in that channel for a few hours to
days, but the soil just a few inches below the surface may stay moist for
days to weeks depending on the depth.

I might guess the seeds sprout during the aftermath of a good rain, which
is probably during the hot summer, and if the soil stays moist long enough
they may survive to the next rain - hoping that arrives before they wither
away. Because the rain is so unreliable they probably take a long time in
habitat to get large enough to bloom, and I would predict leaves wither as
seeds ripen. The developing fruit probably sucks water from the bulb,
which will then need to replenish its stores and grow through a few rain
episodes before another bloom cycle. The green bloom stalk probably
produces quite a bit of food through photosynthesis.

The plants probably don't produce leaves every year, but only after rain.

Leo Martin
Phoenix Arizona USA

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