In the downtown sections of cities, where large buildings dominate the scene, and where the streets are covered with concrete to facilitate the movement of pedestrians and automobiles, the needs of trees, bushes, and grass have been engineered out of the city. The genius that builds a city can, with a little extra ingenuity, engineer into the city conditions that allow these plants to grow.

The native plants of the prairies are tall grasses. If residents of cities built in prairie regions desire something other than tall grasses for their city vegetation, they will have to engineer into their city those elements necessary for whatever plants they have chosen. In desert regions, only those species acclimatized to intense heat, solar radiation, high winds, and other extreme conditions will thrive, unless the environmental requirements of other species, particularly water, are engineered into the city to accommodate them. Palm Springs, California, is so engineered. Cities in deciduous forest regions, with trees surrounded by pavement, their roots cut by sewer and waterlines, must also learn to accommodate city vegetation in their engineering plans.

In applying the strategy of the mature plant community to the public areas of the city, the underlying assumption is that, because of the natural processes of selection, genetic adaptation, and ecological adaptation, mature plant communities present the most stable configuration of the vegetation and hence require the least amount of maintenance for their upkeep.

If more elements of the mature community are incorporated into the city not only will the city become more livable in the sense of providing habitats for more different species of living things, but the city will be less expensive to maintain and more desirable aesthetically and culturally.

In order to maintain and enhance the street plantings in our cities, we need to plan ahead. We need to plant seeds or saplings next to the mature trees so that our street vegetation is at many stages of growth. When an older tree dies, is struck by lightning, or is blown down in a high wind, its replacement should be at the site, ready to fill the gap in the community. In considering the street plantings in our cities, there is no need to accept a monotypic culture in which trees are spaced uniformly in a single file down the street. We could be more adventurous and follow the design of nature, where the vegetation is at varying stages of growth and the design more haphazard. Should the street trees be in a single file? Should they be staggered? On wide boulevards, should there be as many as three or four trunks between street and sidewalk? This last, for instance, could reduce noise pollution for the pedestrian.

Vacant lots do not have to be the ugly scars they are now. Wild berry seeds scattered on a vacant lot and wetted down with a firehose, for instance, would provide a flower with a pleasing odor in the spring and wholesome fruit in the summer. Wild blackberries and wild raspberries will grow in very poor conditions and need no attention. Sumac, a weed which turns a beautiful red in the spring and fall, would grow very quickly on a vacant lot. It would provide a pleasing aspect, a sanctuary for birds, and would hide the litter with which vacant lots abound.

Trees do not have to be removed from building sites, except those actually on the spot where the building is to go. Nor is it necessary to remove all the trees along a new highway. The argument that it is too expensive to build around trees is a fallacious one. North of Helsinki, Finland, a new city, Tapiola, is under construction. Clauses have been written into the building contracts which place a monetary value on each tree at the site. Except for those trees which the plans specify must be removed in order to accommodate the building, the contractors are fined for any tree damaged or destroyed. How much is a tree worth? Perhaps nobody knows, but it is worth at least what it would cost to replace it. To dig, bail, and transplant a fully grown tree that took decades to grow would probably cost several thousand dollars.

If we want plants in our lives, if we want the natural vegetation of the city to thrive in streets and public parks, engineering plans for the city must include the needs of the plants. If a homeowner wants a thriving lawn, he must provide soil and fertility conditions that support the vigorous growth of grass, and he must buy and use a lawnmower. Similarly, if elm or sycamore trees are to shade the residential streets of the community, those conditions that favor the growth of elm or sycamore trees must be provided.

Let us relate the problem to the space age. If we wished to send a full-grown elm tree to the moon, we would have to provide a space capsule into which we had engineered the climatic and environmental conditions necessary for the well-being of an elm tree. Precisely the same conditions that prevail in that space capsule are necessary for the survival of the elm tree on earth. The survival of the elm is contingent upon those conditions no matter where it is grown.

One day, it may be possible to look down from the Empire State Building and see a canopy of green below, or from the street near the Empire State Building it may be necessary to go to an opening in the trees in order to see the top. All that is necessary to bring this about is our desire to do it.

—Theodore W. Sudia