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pierre laszlo

 
Plants

Botany, which I did study awhile in my youth, holds a continued interest. Plants are remarkable organisms. In writing about them, in these small vignettes I try to combine the scientific and the cultural, the bucolic and the utilitarian, and to convey some of my sense of wonder - in brief to try and emulate some of the eighteenth-century natural historians, with the information now available to us.



Yucca brevifolia (Agavaceae).

This tree — the Joshua tree, to use its common name — has the Mojave desert — in the states of Arizona, Utah, California, Nevada— as its habitat: at elevations ranging between 600 and 1 800 m (2 000-6 000 ft). It towers over a shrub canopy that usually also includes sagebrush, blackbrush, Mojave yucca, buckwheat and creosote bushes.
The Joshua tree somewhat resembles a genealogical tree, with branches springing perpendicularly to the trunk and to one another. There are no tree rings, but a spongy pulp material instead. The plant grows from a seed or from a rhyzome of an earlier existing tree. The growth rate is astonishingly slow, 10-20 cm (4-8 in) the first year, only 10 cm (4 in) in subsequent years. It can live up to three centuries. 
It is only after the plant has grown 25-30 cm (10-12 in) that it develops its narrow, sword-shaped pointed leaves. As for the flowers, the tree has to reach 2-3 m  (8-10 ft) before it starts to produce them. In early spring, the stalk is covered with green pods, with 7-9 buds in grouped clusters on each new branchlet. 
Inflorescences appear once or twice every year, rarely on the same branch. The white flowers, usually visible from the end of February until April, have partially opened petals. Flowering depends on earlier rainfall and on a cold winter. 
Yucca brevifolia is remarkable for its symbiotic relationship with its pollinator, a tiny white moth, Pronuba tegeticula synthetica. The moth collects the sticky pollen, gathers it into a ball that it deposits, together with its own eggs, into the pistil.
On a souvent besoin d’un plus petit que soi, according to La Fontaine, a French seventeenth-century writer : ‟one often needs someone smaller than oneself.‟ The smaller entity can make you live and be prosperous, as is the case with the Joshua tree — or with the microbiome in our guts. It can also kill you, as with pathogenic bacteria. Or, among plants, Ponderosa pines infested and killed by Dendroctonus ponderosae, a beetle whose larvae devastate those incredibly handsome trees — a blight currently affectng them along the entire ranges of the Sierras and the Rocky mountains, from Canada to Southern Colorado and California.
Why the name Joshua tree? It was thus named, allegedly, by Mormons during the nineteenth century. The name, Joshua tree, is out of the Bible. The biblical reference is very American: for two main reasons, the religiosity of the people; their anti-elitist distrust of a high-brow education, in the European style, high on Greek and Roman antiquity. Hence, to Americans — to Europeans much less — the Bible is both a sacred and a standard reference book. The name of the Joshua tree, together with the swearing-in procedure at a trial, Congress committee hearing, or with a new President, is a reminder.

 
Castanea sativa (Fagaceae)

This species is native to high forest areas of western Asia from Iran to the Balkans. From there, domestication brought it to Western Europe. Chestnut trees are impressive in size, maturing to 20-30 m tall with a trunk growing to as much as 2 m in diameter. The natural life expectancy is in the range of 200-800 years. Some trees in Europe are reported to be over 1,000 years old.
The leaves are large (to 15-25 cm long , 6-10”), coarsely-toothed, oblong-lanceolate, dark green,, each leaf showing about 20 pairs of prominent parallel veins. 
Flowers are arranged in long catkins of two kinds, every tree carrying both kinds. Some catkins are made of only male flowers, which mature first. Each flower has eight stamens. Near the twig from which these ale flowers spring, grow small clusters of female flowers. Two or three flowers together form a four-lobed prickly calybium, which ultimately grows completely together to make the brown hull, or husk, covering the fruits. Flowers are pollination-incompatible, at least two trees are needed for fertility. The prickly husks, each containing three to seven brownish nuts fall from the tree in October. The nut output peaks at 35-50 years.
Since its inception in mid-twentieth century, history of mentalities has been popular. It focuses on cultural differences such as, for Americans, the can-do attitude, or their multi-tasking habit. 
I choose to describe here — this is my second entry on chestnuts in this series — a French phenomenon, the downfall of the chestnut as a harvested crop, in-between the nineteenth and the twentieth centuries. My wife and I live, at least for part of the year, in southwestern France, in a region where lingers a cult of the chestnut, as embodied by a chestnut festival, which various villages host during the fall. 
In a not unrelated custom, for some time during the fall in European cities, vendors set themselves at street corners selling roasted chestnuts. They are harbingers of the coming winter. But their presence is also a historical reminder : many among their clients, nowadays city dwellers, came originally from the countryside, where chestnuts were an essential crop in the past. 
How and why did the downfall of chestnuts, as a crop in France, come about ? It antedates and is clearly independent of the blight, that came from Japan in the 1890s, and devastated chestnut trees in both Europe and North America — wiping them out in the latter region. 
In mid-ninetenth century, chestnuts occupied in France an area of 580,000 ha. in 1975, it had shrunk to  32,000. Total production amounted to 512,000 t in 1880, but only 42,000 in 1976.
The explanation in terms of mentality has the rest of the country looking down on areas of chestnut growth and consumption, as populated by lazy, good-for-nothing people. A standard joke has a journalist visit one such region: ‟what are the local resources ? Chestnuts. How interesting, what can you tell me about it? How do you grow them, how do you harvest them? Well, the wind shakes the trees and the chestnuts come down. We then pick’em up. And what if there is no wind? It is a bad season.‟  
Can you believe an order-of-magnitude drop in production caused by the rest of the country looking down on you? At least part of the explanation is, more realistically, exodus from the countryside, that the building of railroads encouraged during the second half of the nineteenth century.   
That the downfall of cultivated chestnut trees came about from bumpkins being lazy amounts to just an old chestnut — an expression originating in Victorian England, from people telling one another the same stale story heard initially in the theater.