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Once fall arrives, so does the barrage of advertisements for fabulous shopping adventures; it’s the holiday buying season. Traditional mail is full of catalogs, our email boxes are stuffed with electronic coupons that we may or may not use, and commercials on TV are even more plentiful and louder. Department stores have had their holiday decorations up for at least a month as we all know. Of course, not everything is pure commercialism; this is also the time when evergreen trees begin to come into prominence.

For most of the year, pines and junipers are simply the anonymous trees on the mountain.  As the brown leaves drop from deciduous trees though, that deep green of the conifers becomes particularly welcome. This is clearly one reason why Christmas trees are almost invariably evergreen conifers.

When these plants are at their most visible, unfortunately, any problems they’ve been experiencing show up dramatically.  You’ve probably seen the effects already, but let me give you some examples.

Most of the time, Italian cypress has a stately column shape that can make anyplace look - majestic. That changes when its branches have been bent down and pushed out by nesting birds. Sure, that’s annoying, but it won’t kill the tree. An infestation of spider mites on the other hand, transmogrifies the deep green foliage into a grayish green – notably unhealthy.  Nothing’s quite so creepy as a brown Italian cypress skeleton, the end result.

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Some problems tend to be less obvious. In fact, there are times when a problem could be confused with a natural, healthy event. This phenomenon isn’t limited to evergreens, certainly.  Sunscald on leaves can be mistaken for variegation, for instance. A heavy fruit load on a very young tree might seem like a good thing, but it can weaken the tree and limit its production for at least the following year.

But back to evergreens. Since conifers become so prominent around the holidays, it seems like a good time to talk about them and some of the problems they develop. Any effects of neglect during the previous year, or years, are on display. Many of the pines along some streets never seem much of anything and when we are noticing them more, they look worse. Pines, and other conifers, often demonstrate their suffering by producing a bumper crop of cones.

 What we look for in pines and their relations is a beautiful pyrimidal shape, although that isn’t always the shape they take. Even though some, like pinyon, have particularly round canopies, that’s not what we generally look for. I guess we expect them all to look like Christmas trees. 

Gymnosperms – they don’t create flowers or fruits. Instead, their seeds develop within a protective the structure we know as a cone. Actually, not all cones are woody. They can have any number of forms, large and small, brown, green or other colors. Some don’t look at all like a traditional cone. The juniper “berry” is, in fact, a cone with its scales fused.

When a coniferous tree has undergone a period of stress, it can indicate its problems by the dried out needles, the leaves that drop all over. A bare branch is the result. A more surprising phenomenon is the generation of a copious number of cones. This does make sense from an evolutionary perspective. Each seed-bearing plant holds the genetic information essential to the continuation of its species, and has the genetic mandate to “go forth and multiply”.

A pine with many cones on sparsely covered branches is not healthy, although some people MIGHT think otherwise. This can be a case of the plant trying to keep the species alive, when it “thinks” that it, as an individual, won’t survive. The production of all these cones can take much of the resources it has left. Despite this, if the tree is given ample water, soil amended with compost, and followed by application of dilute fertilizer, even a weakened tree may come back.

For KNPR’s Desert Bloom, this is Dr. Angela O’Callaghan of the University of Nevada Cooperative Extension.

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