Tuesday, February 4, 2014

Restless about Natives

Written by Jim Locklear

        It’s hard to imagine that there could be controversy surrounding something like gardening, but an ongoing, heated debate over the issue of using native vs. non-native plants occasionally rears its head, even in Nebraska.

        Dr. Michael Dirr, noted authority on woody landscape plants, has written of his fellow horticulturists, “Friendships are solidified and shattered over native plants.”
        The battle lines are usually drawn by folks who, for a number of different reasons, feel that native plants are the best choice for use in our cultivated landscapes.  Most native plant enthusiasts are content to simply inspire wider use of natives; others, however, are more adamant and take a more activist approach.
        While these things will continue to be debated in the pages of horticultural and environmental publications, the average person just wants to know what’s the best plant for their landscape.
        A native plant is one that occurs or occurred naturally in a particular region.  Sometimes this definition is tightened up by tacking on the phrase, “before European settlement.”  The key, however, is how you define the region.
        The boundaries of the region in question are most often man-made, such as a political unit.  However, the fact that a plant is native to a particular state, like Nebraska, is not necessarily an indication of how well it will perform as a landscape plant across the state.
        Limber pine, for example, occurs in Nebraska, but only in one small population west of Kimball near the Wyoming line.  White oak just makes it into Nebraska in the southeast corner of the state.  While both are natives, they have extremely limited distributions at opposite ends of Nebraska, and do not always perform as well outside of their ranges.
        Some plants may be widespread, and quite hardy, but are not appealing as landscape plants.  An example is box elder, a smaller tree that occurs across Nebraska but which lacks much ornamental value and therefore is not often grown as a landscape plant (one horticultural writer labeled it an “alley cat” tree).
        The great advantage of natives is that they are well adapted to local growing conditions and should, therefore, require less water, fertilizer, pesticides, etc. to grow and maintain.  There is also less chance of natives becoming invasive weeds, since their natural competitors are present locally.
        A less practical, but equally valid reason for the use of natives is that they reflect a sense of the natural landscape of the region, a sense of place.  Many people are tired of landscapes that look like every other place in the country.  Using natives allows them to bring a regional character to their surroundings.
        No plant, native or non-native, is without its limitations.  Bur oak is a magnificent tree, but relatively slow growing.  Green ash is very hardy, but suffers from borer insects.  Sycamores have beautiful bark, but may grow too large for most urban landscapes.
        The most important issue in selecting plants (assuming they are non-invasive) is not whether they are native, but whether they are well adapted to the growing conditions they will face in the landscape.  Few people would observe bald cypress in its natural setting in a southern swamp and imagine it would grow in Nebraska.  Yet this non-native has proven to be a hardy, adaptable tree in Nebraska that can tolerate both wet and dry conditions.

1 comment:

  1. And there's the importance of sustaining wildlife, especially beneficial pollinators. More and more people are looking to garden for aesthetic, practical, and more ethical reasons -- the ethical being an awareness of the loss of larger ecosystems beyond the garden gate and the species within those large ecosystems (monarch butterflies, for example). Native plants also serve as host plants for insect larvae. I'm not sure there's anything wrong with an activist approach unless it's just completely rude and overbearing. The new landscape design is one that is ecologically aware of place, and perhaps even aware of the issues of climate change, the 6th great planetary extinction, and the loss of place that big ag and McLandscapes create. Gardens are political statements -- vegetable gardens sure are and no one takes issue with them -- so why not ornamental gardens? Why not ornamental gardens with native plants that support native pollinators (bees, butterflies, wasps) that are also planted among veg gardens and even farms thus increasing yield?