Journal archives for December 2018

06 December, 2018

Sesbania (Riverhemps)

In August, 2018, while visiting my parents in Jefferson County, Texas, I saw a really interesting looking plant growing in a ditch. It was at least 6-7 feet tall, with yellow flowers hanging in bunches. After driving by it several times, I talked my husband into stopping on the shoulder so I could jump out and take a quick picture. It came up on iNaturalist as “Rattlebush” (Sesbania drummondii.) It's a plant in the legume family, and has the pinnately compound leaves typical of these plants, but it's as big as a small tree. It clearly wasn't planted, so I wondered where such an odd plant had come from. On our drive to Houston a few days later, we saw these plants everywhere! I grew up in Southeast Texas, but I had never seen (noticed?) one of these before in my life! I had observed a Big Pod Sesbania Sesbania herbacea in the DFW area, and I soon realized these two were related. When I got back home, I found several more of both types of Sesbania. Next, I found a similar looking plant that turned out to be Bladderpod, Sesbania vesicaria, and soon I saw several more of those. Once these plants developed seed pods, I really loved them! Each had a totally distinct kind of seed pods - that's the kind of plant I like! You can definitely tell them apart, even in pictures! There are also several other species in the Sesbania genus, but those don't grow around here, and I’ve never seen them. So, I won't address them.

Here’s the rundown on these three:

All three:
Erect, non-twining, herbaceous plants with leaves even-pinnately compound, without tendrils or spines, growing up to 12 feet tall in a single year. The leaflets are entire and are not glandular-punctate. Flowers solitary or in racemes of 3-30 flowers. Fruits are non-segmented, several seeded.

If they have fruit (seed pods,) it’s easy!
The seed pods on Rattlebush ( Sesbania drummondii) are about 2 - 3 inches long, 4-sided, winged, and typically have 3-7 seeds per fruit, while Big Pod Sesbania (S. herbacea) has seed pods that are much longer and narrower, do not have wings, and each pod has many tiny seeds. Bladder Pod (S. vesicaria) has seed pods that are about the same size as those of Rattlebush, but they are two-sided, without wings, and usually have 2 seeds per fruit. In Bladder Pod, as the seedpods mature, they separate into a thicker outside layer and a papery- thin, inside layer, which is also quite distinctive.

If fruit has not yet appeared:, the flowers are still quite recognizable: Bladder Pod usually has several flowers in short racemes, but sometimes the inflorescence is a solitary flower; flowers are reddish brown to orange or yellow, often tinged with pink or red. Each flower is 6-9 mm long; usually there are 1-6 flowers per raceme, but occasionally up to 12. Big Pod Sesbania has yellow flowers, 2-6 per raceme. Rattlebush has yellow flowers, sometimes with red lines, 10-30 per raceme.

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Posted on 06 December, 2018 02:13 by lisa281 lisa281 | 5 comments | Leave a comment

15 December, 2018

Turkey Tangle Frogfruit

May, 2018

Sometimes my insistence on taking pictures of tiny, insignificant little "weeds" pays off. That's how, on a otherwise boring walk around a neighborhood of cultivated plants, I "discovered" Turkey Tangle Frogfruit. Maybe the plant is not that impressive looking, but that's the best name I learned all year! It's almost impossible to say it without smiling! The only problem is that I have NOT been able to find out WHY it's called Turkey Tangle Frogfruit. And someone is always asking! I usually just ask kids why they think it might be called Turkey Tangle Frogfruit! (See! I just love saying it!) Their answers can be pretty entertaining, but I would like to know the REAL story! If anyone knows, please share!!

Anyway, on to ID'ing these. The "flower" of frogfruit is very pretty, but so tiny that you have to get down there on the ground to even notice it. It's actually made up of many tiny, four-petaled, white or pink flowers around a dark center. After you've identified it once, it's very recognizable as frogfruit (or fogfruit, but that name is not as much fun!) However, it turns out there are several species of frogfruit, at least four that occur in North Texas. Turkey Tangle Frogfruit (Phyla nodiflora) is by far the most common, but Lanceleaf Frogfruit ( Phyla lanceolata) is also fairly common. Two less common species, Diamond-Leaf Frogfruit ( P. fruticosa)* . and Wedge-leaf Frogfruit (P. cuneifolia) also occur.

The two most common types of frogfruit in North Texas are Turkey Tangle Frogfruit (Phyla nodiflora) and Lanceleaf Frogfruit (P. lanceolata)

In P. nodiflora (Turkey Tangle Frogfruit), the leaf is teardrop shaped (oblanceolate) with the widest part of the leaf beyond the middle, and the leaf is toothed only near the end, less than half the length of the leaf. In P. lanceolata, (Lanceleaf Frogfruit) the widest part of the leaf is near the middle, and the teeth start below the middle and cover more than half of the leaf.

Each of these common types of frogfruit have a less common type with a somewhat similar leaf shape. If the leaf is widest beyond the middle, it is most likely P. nodiflora, but you still have to rule out Wedge-leaf Frogfruit (P. cunefolia).

In P. cunefolia:
• the leaves are small and have only a few (1-3) teeth per side.
• the flower stalks are short: not much longer than nearby leaves, and often even shorter.
• The inflorescence (the little bunch of tiny flowers) is short and round, and large in proportion to the tiny leaves.

In contrast to P. nodiflora, where:
• the flower stalk is longer than the adjacent leaves, usually much longer.
• The inflorescence becomes long (cylindrical)

If the leaf’s widest part is near the middle, it is most likely P. lanceolata, but you still have to rule out Diamond-Leaf Frogfruit (P. fruticosa.)* Luckily, the leaf looks quite different.

In P. lanceolata:
• The ellipse shape of the leaf has a nice, even arc – with the widest part at the middle, tapering to a point at each end. The teeth cover more than half of the leaf on each side, from below the widest part to the tip.

In P. fruticosa:
• The leaf is NOT an even arc: it gets to its widest part before the middle, then tapers to the end. The leaf does not have teeth below that widest point. The leaf is often pleated (folded like a fan) and the teeth are also more spread apart (divergent) than in other species.

*USDA Plants database lists P. strigulosa as synonym for P. fruticosa

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Posted on 15 December, 2018 22:23 by lisa281 lisa281 | 3 comments | Leave a comment

27 December, 2018

The Elm Project, Part 1

I think of the elms in our area as coming in three pairs: two introduced species, two species with large leaves, and two species with small leaves. All of them have leaves with toothed margins and asymmetrical bases, and have a “fruit” called a samara, a winged seed. Most have double-serrated margins, that is, each tooth has a break in it, making a second little “tooth.”

In this journal, I’ll address the two introduced species, Chinese (or Lace Bark) Elm, and Siberian Elm. These two differ from the four native species in a couple of ways. First, the leaves are only slightly asymmetrical at the base: often the shape of the leaf looks symmetrical, except that the central vein is off-center. Secondly, the leaves are quite smooth on the top. The leaves are usually toothed, but not double-serrated. The samaras are smooth, both on the surface and around the edges. They never have corky “wings” on the branches or twigs.

LACEBARK/CHINESE ELM (ULMUS PARVIFOLIA) This one is being planted a lot lately, but doesn’t occur here naturally. This tree is most easily recognized by its bark. It has a very distinctive "lacey" bark, flaky and mottled, often with orange-ish underbark showing through. The leaves are smooth on the top surface and are fairly symmetrical at the base, although sometime inequal. The leaves are typically once-serrate. Other than Cedar Elm, it is the only elm occurring here that flowers and seeds in the late summer/fall.
• Here’s an observation by @fratto of a Chinese Elm that shows both the distinctive bark and the leaf shape:

DWARF/SIBERIAN ELM (U. PUMILA) This species is not commonly planted here. There are a few reported here, though, so I’m including it. These are small trees, with leaves similar to Lace Bark Elm: fairly symmetrical at the base, and once-toothed, and smooth on top. They flower and seed in the spring, have seeds that are completely smooth, and do not have the flaky bark of Chinese Elm.
• See this observation by @bob777 of a Siberian Elm

In Part 2, I'll address the two elms with large leaves, American Elm and Slippery Elm.

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Posted on 27 December, 2018 19:21 by lisa281 lisa281 | 0 comments | Leave a comment