BY DON HERZOG, MINIATURE PLANT KINGDOM AND ALLEN TACY
TREES GREATLY ENHANCE scenes on an outdoor railroad. Just as the trains provide action, trees add a sense of beauty and drama, even a sense of scale. Trees add elegance and color, they draw attention to scenes and frame them. They are the backbone of a layout's scenery.
Few decisions will add more unity or personality to your railroad than your choice of trees. If you want green to be the dominant color of your landscape, conifers would be a good choice. If you enjoy the brilliance of fall colors, choose a deciduous tree. And, of course, tree selection will guide your use of shrubs and ground covers.
Some evergreen shrubs resemble fruit trees. Or imagine how magnificent a miniature oak might look in a park beside your favorite depot, helping to tie together the railroad and the rest of your backyard.
The size of a tree should relate to the size of its setting. For example, a two foot tree looks at home in a smaller area, say six by twelve feet. On the other hand, a tree of five feet or even taller might be completely appropriate in a larger setting, particularly if the scene where it grows were also large.
The following are examples of plants you may use for trees in an outdoor layout. None grows higher than five feet and each has very small leaves to maintain the scale of the railroad. Yet the special character of each makes a dramatic statement.
Slow growing middle size conifers such as mountain hemlock (thuja mertensiana) and alpine fir (abies laziocarpa) are quite suitable for larger layouts. Eventually they become too big for our scale, but they require more than a century to reach full height. Spruce and fir varieties from the Pacific Northwest grow slowly in hotter and drier climates, only about an inch or so each year. In their native environments they may grow at two or three times that rate. Junipers such as the San Jose Juniper produce a gnarly bark you may expose by pruning back the low branches.
Many small leafed deciduous trees become beautiful specimens if you prune them regularly. Even without pruning the Hokkaido elm is very striking. It will reach a height of twenty-four inches with a four inch diameter trunk after about thirty years but ten year old Hokkaido elms also look impressive. A larger version of Hokkaido, the Seijo elm, reaches a mature appearance in four to six years but it does require pruning.
If you prefer the "weeping willow" look, consider Trost's Dwarf (betula alba pendula). It is a lace leaf weeping white birch. After five years it grows to two or three feet and its white bark starts to peel. It looks like a miniature Japanese maple, it has a reputation for producing beautiful fall colors, and it's easy to grow.
You may also find plants to resemble apple and orange trees, right down to the miniature fruit. Ten year old cotoneaster microphila thymafolia and corokia cotoneaster require pruning, but deliver results.
Many nurseries carry older plants with several years' growth so you won't have to wait as long as a century for the appearance you want. They do cost more but you'll need only a few, so the tradeoff may be worthwhile.
Next time we'll look at how to create a forest and discuss the conifers you'll need to do it.