D.chrysolepsis and U.volubilis

Barry Meyers-Rice (barry@mips3.as.arizona.edu)
Mon, 25 Jul 94 13:30:59 MST

Two observations from the greenhouse. The first is with my _U.volubilis_.
I've been growing this well for several months, although the leaves
(linear, < 1.0 cm long) have had a slightly stunted look to them. TAYLOR
says this species grows as a terrestrial or affixed aquatic. For
simplicity I've been growing this as a terrestrial. It's been doing well
enough that I've been able to take a few (successful) leaf cuttings. But
after reading cultural notes by Slack and field observations by Erickson, I
decided to take the plunge, so to speak, and grow it as an affixed aquatic.
I have raised the water table for my largest plant so it now stays underwater
all the time. After about a month it has started producing leaves about
2--3 cm long. I think it is happier. I'd sure like this plant to flower.
I am hoping to increase my population of the thing so I could start
distributing it. As it is, I don't know of anyone else in the US growing it,
and I'm uneasy with this situation.

The second note: Anyone out there growing _D.chrysolepsis_? I've got a
plant that Don Burden sent to me. The plant is very interesting, an erect
habit with petiolate leaves+lanceolate lamina, somewhat similar in total
effect to _D.scorpiodes_ except much larger (total height of plant 4--5 cm).
Anyway the really interesting thing about the plant is that each petiole
is twisted about 20--60 degrees (not bent, but rather spirally twisted
along the petiole axis). As a result, each lamina is not held level w.r.t.
the ground, but tilted. All the leaves are twisted the same way, resulting
in a plant that is slightly spirally contorted as viewed from above, like a
propeller (except not so dramatically). Very interesting. I'm reminded of
a clone of D.capensis which supposedly exhibited this behavior. It was called
`Merry-Go-Round'. I have some seedlings from a plant with this name, but they
are very small and it will take some time to see what's happening with them.

My plant is growing in part shade in the greenhouse, along with all the
other plants. I do not think this is a cultural anomaly, since it is hard
to explain an effect that would cause all the leaves to distort in a
centrosymmetric pattern like this.