Phyllostachys aureosulcata - Spectabilis with large leaves

[Tarzanus]

Did any of you notice something like one of the culms on my Spectabilis. Leaves are usually thin and long, but one culm had made large thick leaves instead. At first I thought it's because the shoot came up later than others in the mid summer.

First image shows normal spectabilis leaves, second photo the strange looking glossy-large leafed culm.

[Rufledt]

Can you post some dimensions? That looks kinda familiar but I may be thinking of another plant than spectabilis. Ill check when I get home tonight if the sun is still up.

[Tarzanus]

I'll do it tomorrow when sun comes up again. Overall the laves are similar in length, but are two to three times wider. Normally, leaves are slender, long but thin. The leaves I'm asking about could be in juvenile form or something. On the other hand, I don't remember seeing leaves like that even on small division, when I bought the bamboo.

[needmore]

I think that occurs on new culms on juvenile rhizomes, or something like that but I see it here now on some species.

[oobmab]

I get that on juvenile shoots of several of mine (rubro, praecox, yellow groove). One plant has a leaf that is over 25.4 cm (10 in.) long and 38 mm (1.5 in.) wide. Looks like a pseudosasa japonica leaf.

What exactly is a juvenile shoot, btw?

[dependable]

Seems to me that a lot of bamboos are fairly adaptable to different conditions. When they are younger (in grove development) they seem to be able to adapt to soil, water, light conditions with a variety of types of plant growth habits. These may include differing leaf size and density, type of roots produced, culms drooping horizontally into more well light areas and so on.

Old, stagnant groves are another story, and put out homogenious culms and leaves.

This is a vauge observation, but seems to apply to the Phyllos.

[Tarzanus]

I picked one of enlarged and typical branch and scanned them together. I can even see some mite damage.

Largest leaf is 13.5 cm long for comparison.

[oobmab]

I think this is a brilliant design feature of some bamboos that when rhizome mass is small, the plant opts for a proportionally greater leaf mass (compared to culm mass) in order to maximize solar collection area (and thus rhizome growth). Then when rhizome mass reaches a certain point, culm mass increases for strength (and thus height), and leaf size takes a back seat and normalizes.

[Tarzanus]

The thing is, that darn thing exploded this year. I've noticed rhizomes traveling all around the place, and I'm cutting and taking them out lately. I also have divisions (small divisions) of the same plant. I took bare rhizomes with no existing green leaves attached and those divisions made it and they all ended up with small leaves. If it's juvenile form (oobmab - before seedling matures enough it doesn't show all characteristics of adult plant, we call it juvenile. Same thing can happen if you drastically prune it, dig it out and replant it or somehow damage a lot of it's rhizomes/culms) that makes large leaves, those divisions didn't enter it. I placed them into pots, some of them really small and shallow, they are all healthy and have thin leaves.

One other possibility would be a lot of water. With a lot of rain this year, there was standing water all around the bamboo, and this one is located in one of the most water exposed location. Sometimes there's standing water around it. Other culms in it's vicinity had been developed before the most of the rain fell, so it might be related. I hope big leaves survive the winter and I'll see if next year brings more of them or if perhaps they turn "normal". I almost like those large leaves better though.

[needmore]

I include juvenile to mean that new rhizomes may fire off immature buds and the resulting culms look like a juvenile planting/newly dug plant's initial new culms.

EDIT: I would also add that on top killed species, I often seen large leaves the following year, such as in Steve's photo below.

[stevelau1911]

In terms of leaf size on juvenile plants, I think phyllostachys shanghai III may beat out every other species, at least with what I've ever seen. It's even bigger than moso seedling leaves.

These culms are 6-8ft tall, and those are normal dried maple leaves just to give a comparison on the leaves. I think some of them are close to 9 inches in length, and the most leaves I've seen so far on a single branch is 13, meaning that it is just loaded with foliage.


I really doubt it will be this foliage heavy, or have leaves this big ever again once culms get bigger next year.

[needmore]

In terms of leaf size on juvenile plants, I think phyllostachys shanghai III may beat out every other species, at least with what I've ever seen. It's even bigger than moso seedling leaves.

These culms are 6-8ft tall, and those are normal dried maple leaves just to give a comparison on the leaves. I think some of them are close to 9 inches in length, and the most leaves I've seen so far on a single branch is 13, meaning that it is just loaded with foliage.


I really doubt it will be this foliage heavy, or have leaves this big ever again once culms get bigger next year.

My dulcis are largest...

[Rufledt]

I checked my spectabilis. The old culms (pre division) have much smaller leaves than the new shoots, so that seems to agree with what others have said.

[oobmab]

I include juvenile to mean that new rhizomes may fire off immature buds and the resulting culms look like a juvenile planting/newly dug plant's initial new culms.
EDIT: I would also add that on top killed species, I often seen large leaves the following year, such as in Steve's photo below.

This is exactly what happened to mine, except some experienced only partial to total leaf kill this past winter. All of the new shoots in spring were juvenile with big leaves, but later in the year normal type culms with normal size leaves started coming up (still are even this late in the year).

[oobmab]

Check out this bad boy; almost 270 mm (10.5 in.). Have to admit that I did pee on this one a lot.