Herbaceous Trees

P91005KPalms are like ‘Red Delicious’ apples. It seems that most people dislike them; but they also seem to be very popular. Seriously, if only a few people like ‘Red Delicious’ apples, why are they so common in supermarkets? If most of us dislike palms, why are they so common in the San Jose Skyline?

I suspect that palms really are as unpopular as they seem to be, but that they are also very conspicuous within their situations. Not only are they focal points of the landscapes in which they live, but most types eventually stand as tall as the tallest trees in the neighborhood, and some get significantly taller. They are innately the most prominent trees within their neighborhoods.

Palm are not like other trees though. Arborists may classify them as ‘herbaceous trees’. They are foliar plants while young, producing increasingly large leaves from terrestrial rosettes. They only ‘launch’ and start to develop their trunks after the formerly terrestrial rosettes have grown wide enough to do so.

Not only are their trunks no wider than their associated foliar rosettes, but they get no wider as they grow taller. The base of a trunk of a palm is as wide when the tree is only a few feet tall as it will be when the tree grows to forty feet tall. Mexican fan palms are only wider at their bases because they start out like that.

Palms with slender trunks can launch much sooner than those with wider trunks. It does not take long for their rosettes to get as wide as their trunks. Canary Island date palms have rather plump trunks, so may need to mature for many years before they launch.

Yuccas and dracaenas are not really palms. Their trunks expand and develop branches as they grow and mature.



P71108A plant that clings to another plant for support without parasitizing it is an epiphyte. Some do it to get a bit more sunlight closer to the ceiling of a dense forest. Others do it to get up off of the forest floor to avoid competition with conventionally terrestrial plants. Maybe some just want to avoid grazing animals. It is often difficult to determine why plants do what they do.

Spider plants, ephiphyllums and many types of orchids, bromeliads and ferns are some of the more familiar epiphytes. Most do not actually cling to trees. They instead live in the crotches of limbs where debris from the foliar canopy above accumulates. Either way, they do not need much organic matter in which to disperse their roots, and some need none at all. Many collect what they need from the air and precipitation.

This is not about an epiphyte.

It is about a Mexican fan palm that thought it was epiphyte.

You might have though that the picture above depicts a common Mexican fan palm next to a surly London planetree. With closer inspection, you will notice that the palm lacks a trunk at ground level. The utility pole visible below the palm is not attached to it, and does not support it. Yet, the palm does not just hover there. It grew from a cavity in the London planetree.

Most of us know how many plants self sow in weird places. Sometimes they appear where they are welcome. Usually, they end up in pots with other plants, too close to pavement, or in rain gutters that have not been cleaned out enough. Of course, big trees commonly appear under utility cables. Once in a while something self sows in a decaying cavity of a tree.

Most of us have enough sense to remove self sown trees and plants that appears where they can not live for long without causing problems. Those of us who hire gardeners tend to trust and hope that the gardeners would exhibit the same sort of common sense. After all, that is part of what they are payed significant money for.

Unfortunately, Mexican fan palms are not epiphytic. They are just too heavy, even when young.