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by James P. Engel, © 2010
I was revisiting a landscape I installed a few years back. I like to look at landscape a few years later to see how they have weathered the test of time. To my shock and dismay the landscape had been changed from the original design. Some plants remained but others had been removed and still others had been replace with off the shelf plants. it looked a lot like the original landscape. I racked my brain. At the time, the owners raved about their new landscape. What went wrong?
I was too shocked and maybe self-conscious to stop and ask why. But the question nagged at me. Was it my design, where had I failed, should I have taken more time educating the client. had I asked the right questions or was it the homeowner? Had they changed their mind about the landscape or more likely new owners had moved in and their aesthetics were completely different.
This experience kept coming back to me. I have invested a lot of energy into growing native plants and promoting them to the public. I work hard to change peoples thinking about native versus exotic plants, their landscapes and larger ecological issues. The population is enormous, the true converts are few, and this was a definite setback.
The issue was larger than just this one landscape. What would happen to all the other landscape over time. How permanent are these plantings and what lasting impact are they making in conserving native plants or improving the larger environment. If a new landscape can so easily be undone, is there any permanence to what I or anyone else is doing? I began to contemplate the future.
I considered three likely scenarios. On one end of the spectrum are the few people who are committed to the principal of natural landscaping. They will allow the landscape to follow its intended design and mature into a natural looking landscape that will be aesthetically pleasing while also providing other ecological benefits. On the other extreme are home owners who will find the natural landscape and native plants not to their aesthetic taste and proceed to convert it to a more traditional formal landscape filled with showy exotic specimens and sheared mushroom shaped shrubs. These people just want their landscape to look good and blend into the neighborhood so they can be like everyone else. The rest of the people will fall somewhere in between these two poles.
Over time all landscapes will be begin to mature and require pruning and maintenance. If the owner is not aware of the long range plan, they may gradually be replaced with common non-native landscape plants, as the natives die or out grow their space. The design intent may be misunderstood and altered over time through ignorance or simply because of a different aesthetic taste.
I began to reflect on a longer time scale. Even if the design is maintained and the native plants survive. What is the significance to the local or larger environment? A realistic assessment is “NOT MUCH”. Planting a few native plants in your back yard when the forest parcel down the block is bulldoze for a new subdivision, demonstrates the lopsided inequality between the efforts for preservation and the destructive forces taking place in our communities.
As a nursery I supply the needs of people. I grow plants they want to buy and educate the public in the process. I propagate native plants by the thousands and sell them to willing buyers, who plant them in their yards with the expectation they will grow. Selling plants is good for my customers, the environment and me. Or is it? I always thought I was making some environmental contribution in the process. But is this the best way to encourage native plant conservation? How does this help conserve native plants? How much habitat is created in the process and how long does this habitat ?
My reflections forced me to confront many closely held beliefs and assumptions about what I was doing and whether I was making any lasting contribution to native plant conservation. I began to look for new answers and analyze my old belief system.
The realization finally hit me. We are creating dead ends for the plants we put in our yards. We buy a plant and take care of it for however long it lives and when it eventually dies, we replace it with another plant that we buy from a nursery. We are creating zoos for plants. Our plants are figuratively caged and held captive. They will never be able to live free and reproduce.
The parallel between preserving plants in our yards and what happens to animals in zoos became suddenly clear. In the conservation of rare animals, animals are frequently removed from the wild and kept in modern zoos for display to the public, to safe guard the remaining individuals and also for the purpose of captive breeding to increase their numbers for the eventual release back into the wild. Even if breeding is successful without protecting sufficient wild habitat for the animals to eventually return to, the animals will only live in zoos. They never make the journey back to the wild where they can live wild, reproduce and increase their numbers. Isn’t that always the ultimate goal for conserving animal species? Shouldn’t we view plants in the same light?
By placing native plants into an unnatural setting in our backyards, are we not just creating zoos for plants, the same way we put wild animals in zoos? Unfortunately with plants, I understood that we are still following the old outdated zoo model. We protect a few individual plants for the duration of their life in a safe and nurturing environment, but if that plant cannot pass on its genes to the next generation, what was its purpose for living? Are we not simply putting the plants on display for our personal enjoyment without concern for the long term sustainability of wild populations or helping them repopulate the wild? Conserving plants has larger ecological implications than saving one single species. Plants are the base of the entire food web that sustains all the other organisms in the ecosystem. Conserving and restoring plants benefits all the other species that depend on those plants.
We need to begin to think of plants with the same long term conservation objective as we do with wild animals. The goal of returning the animals to intact wild habitat where they will live wild, reproduce and increase their numbers. How can we begin to grow plants where they can increase their numbers and interact with their environment? As gardeners and plant enthusiasts we need to make the transition from simply being caretakers of plants someone else has grown, to the role of plant propagator and land steward. We need to return native plants to their rightful place in the wild and we need to restore whole plant communities to lands where they have been displaced.
The next obvious question is, how do we do this and how do we do this in an efficient and affordable way? One that can be done on a large enough scale to have an impact and one that can be implemented by the general public.
Propagating plants is not as difficult as it may seem. Nature does it quite efficiently without any fanfare and elaborate equipment. Plants do not actually come from a nursery they come from seed. Nearly every flowering plant produces seed. For most plant species be they trees, shrubs or perennials the seed simply needs to come in contact with soil and then wait for certain conditions to be met for germination to happen.
Native plants in our yards are often brimming with seed, but rarely do they produce any seedlings. The space in our yards is already fully occupied with plants and the surrounding landscape, filled with turf and asphalt, is as inhospitable to germination as the surface of the moon. But seed placed in a suitable environment will germinate, grow and reproduce.
Reproduction in plants is most often hindered by the inability to adequately disperse their seeds to new sites suitable for germination. Plants rarely are capable of dispersing their own seed and are dependant on other species or natural forces for seed dispersal. Seed collection and dispersal is an area where people can really have a direct impact on plant survival. You can increase the reproduction potential of native plants by learning how to collect the seed of these plants. The seed then only needs to be planted in contact with the soil in areas suitable for the seed to germinate and grow.
By dispersing seed you are participating in one of natures most basic services, moving seeds around. Seed dispersal In nature primarily happens by being transported by the wind or water or by being eaten by birds and mammals. Once dispersed the seed lies exposed on the soil surface vulnerable to numerous seed predators and environmental stresses. Under natural conditions 100% of seed is commonly eaten or killed each year. People can provide an increased survival benefit for seed that natural means of random seed dispersal cannot. We know where the best place is to disperse the seed and where the seed will have the best long term chance for survival. We choose the planting site that is best suited for that particular plant species. You match the seed to the right amount of sunlight or shade, soil conditions, and successional habitat. We can choose a site that we know is legally protected or will remain undeveloped in the foreseeable future, to ensure long term survival.
There are opportunities in our yards to create larger and more diverse plantings and habitats, but this is only a first step. Next we need to think in terms of what to do with all the seed we will collect. Where will it have a chance to grow and spread. There is no shortage of land that is subjected to human disturbance and lacking adequate native vegetation. The majority of land surrounding us falls into this category, but much of this land is off limits for the purpose of growing native plants. Residential property, park land, agricultural fields, expanses of mowed lawn and other types of actively managed property is generally off limits. Still a great deal of land remains that could be used to establish native species. Roadsides, ditches, utility corridors, abandoned lots, railroad tracks, stream corridors, unused city and county parcels are just a few of the locations suitable for seeding. Any property that looks vacant and is not being actively managed for lawn and people has potential.
This type of land has a few common characteristics. It is generally ignored by its legal owners except for the specific purpose for which it is owned. such as road-sides and utility right-of-ways. The existing vegetation Is neither planted or managed but occurs by default. Existing plant species were either previously present or have colonized on their own. Many of the species will be non-native. These areas are often overrun with invasive species because of the disturbed nature of the land and absence of a native seed source nearby.
The introduction of seed can be as simple as walking along a path while broadcasting the seed you collected. The next level of care would be placing the seed in contact with the soil. The simplest method involves uncovering the soil with your foot then sprinkling some seed on the exposed soil and then pressing the seed into the soil with your foot, to encourage good soil to seed contact. The third level of effort requires loosening the top inch of soil with a shovel, sprinkling some seed on the soil and then firming the soil with your foot. The whole idea is to mimic nature’s way but use good horticultural practices to greatly improve survival. In the end nature determines what seed will survive and grow. Natural selection still has the final say. The technique requires little effort or time on your part, but only a faith that the process will result in the growth of native plants.
In your role as seed collector and dispersal agent you are serving an age old function like the wind, birds and ants. You become just one more species serving its biological role in nature. It is easy to think nature will take care of itself, but with increased human disturbance comes an increased need for people to play a more active role in nature, helping to offset the negative effects of others. Keep this in mind the next time you pass a plant full of seed.
After healthy reflection I now see my way forward with renewed vigor and commitment. My vision now extends past each individual landscape to the larger landscape. Many questions still remain. What seed should I collect? Where shall I plant the seed? When will I have the time? I can’t wait to get started!
Jim Engel operates White Oak Nursery, a native tree and shrub nursery, and is actively involved in all aspects of habitat restoration.
this page updated Feb 10, 2010