A word about invasive plants

The invasive plant issue is very complex, often clouded by false dogma and misinformation. As a consumer, learn which plants pose a risk to natural areas in your region. Nurseries, in particular mail order nurseries, offer a wide range of plant species and cultivars. It is not our role to tell you which plants you can or cannot grow. By definition, a weed is a plant out of place, and so there are many examples of plants like Tamarix which is a weed in Colorado yet perfectly tame in Minnesota. Nurseries do not support the wholesale banning of plants but rather encourage environmental stewardship. Please buy only those plants that are appropriate for your region.

Use common sense and exercise caution when using cultivated plants in or near natural areas. It does not make sense aesthetically or environmentally to plant Autumn Olive at the entrance to a nature preserve. Natural sites and urban sites require different consideration when choosing plants.

If a particular species is known to be problematic in your area, choose "Solution Cultivars". These are selected cultivars known to be poor seed producers and thus non-invasive. Examples of solution cultivars include Berberis 'Concorde', Buddleia 'White Ball', Euonymus 'Rudy Haag', Rhamnus 'Asplenifolia' and Fine Line Rhamnus. All of these cultivars are poor seed producers and are non-invasive. The ANLA and the Horticulture Research Institute is funding breeding projects to develop non-invasive solution cultivars. Solution cultivars are a local solution to the invasive problem; grow them, promote them and get involved so your state does not ban them along with the problematic plants.

As gardeners, plant lovers and nursery professionals, we need to be careful with our words. Do not cloud the issue by describing an aggressive plant as being invasive. Plants such as ground covers are selected to fill in a bed quickly. They may be aggressive growers but if they do not send unwanted seedlings into native ecosystems they are not invasive. There are numerous websites that list plants as invasive but the plants listed may actually be fine for your local area. Refer to your state's invasive plant council which should be basing their recommendations on scientific research specific to your state.

I agree that as gardeners we need to be responsible and informed.

But nurseries need to be responsible also.

Alot of people do not know which plants are invasive, nor do they know where to look, and often times I have heard "Well, I bought it at the nursery, surely they wouldn't sell something that is harmful or illegal." Customers expect the nurseries to take the lead to help educate them. I find many nurseries lacking in their ability to educate their customers.

In my experience, the staff at the local nursery can barely tell whether the plant prefers full sun or part shade let alone the difference between an aggressive plant and an invasive plant.

There are so many plants to choose from, its best to stay away from the cultivars of invasive species because they are a wild card. They may not propogate as quickly as the original but they can cross with original and their offspring may be just as invasive as the original. Why take the risk of propogating potentially invasive plants when there are thousands of plants to choose from? Often times similar substitute plants are available that are eco-friendly.

Though I do agree that using the term invasive and aggressive interchangeably trivializes the impact that invasive plants have on the environment. ( I know I have said that time and time again. )

Hi Michael, and welcome to DG. I hope you'll stick around and discuss this important issue. It would be interesting for many of us to understand a nursery professional's point of view.

I agree with you and Joepyeweed that gardeners should be responsible and informed, but most people I know haven't given much thought to invasive species. They go to a nursery and see rows of Burning Bush (Euonymus alatus), Japanese Barberry (Berberis thunbergii), English Ivy (Hedera helix) and Periwinkle (Vince minor) and think these plants will solve their landscaping problems, and they do. They don't look beyond their yard.

I don't support the wholesale banning of plants either, but offering these plant as problem solvers with no warning doesn't, in my mind, "encourage environmental stewardship." Should we put warnings on plants? Sounds kinda crazy. So tell me, how do or should nursery professionals encourage environmental stewardship?

On the other hand, I certainly want good nurseries to thrive, and to do that they've got to make money. (duh!) If someone comes in and is determined to buy 10 leyland cypress (X Cupressocyparis leylandii) for her backyard, is it the nursery professional's job to encourage her in another direction? Maybe. Maybe not.

There are certainly no easy answers here.

Please take a moment to run your concept of "Solution Cultivars" by me one more time. I'm having difficulty viewing Euonymus fortunei 'Blondy' and Albizia julibrissin 'Rosea' as "Solution Cultivars" or "Proven Winners".

I didn't say that Blondy® is a solution cultivar; I said 'Rudy Haag' is listed as a solution cultivar for Euonymus. Nor did I say that there is any solution cultivar for a silk tree...

Proven Winners® is a brand name of plants and includes Proven Selections® and ColorChoice® Flowering Shrubs. While some PW plants are classified as solution cultivars, I did not say nor imply they all were - actually, I didn't mention any brand names at all.

As far as 'solution cultivars', NCSU and the University of Arkansas are two universities (among others as well as other institutions and agencies) that are working to develop solution cultivars for what are or may be considered invasive plants. Using NCSU's definition, a solution cultivar is a plant with dwarfed or non-functioning reproductive systems or with seeds that are not easily dispersed.

A lot of people have butterfly bushes (Buddleia davidii) in their gardens but because of their aggressive growth habit and light seeds that are easily dispersed by the wind, they are rapidly becoming a nuisance weed in some places. Research is underway to cross the Buddleia davidii with Buddleia indica to create a plant with heavy seeds that are not easily dispersed.

Of the 300 or so 'invasive plant' species, many are common landscape plants... So yes, I support research to develop solution cultivars. I also support consumer awareness. These are preferable to legislation that bans plants - we have enough laws and regulations now.

Fireweed87 - most, if not all, of the plants you mentioned are being researched at NCSU for development of solution cultivars.

Besides the 300 or so invasive plants that are common landscape plants...
how many other common landscape plants exist that can be used as replacement for the invasive ones that provide similar characteristics without the reproduction problems?

Lets face it folks, there is no shortage of plant material for growers to wholesale. What they produce however is usually the easy to propagate and cheap to grow stuff. Those are the very traits that when let loose in the garden often translate to invasive in a lot of cases. How many of you are on a constant quest looking for the more refined cultivars in specialty nurseries? Diffcult to propagate or slow growing plants are largely ignored by a lot of growers. It is purely economical. I reserve judgement on the solution of the "solution cultivar". Now please excuse me while I go on my weekly hunt to eradicate seedlings from an A. brevipedunculata 'Elegans' whose vine I destroyed last year.

This message was edited Jul 14, 2006 12:49 PM

I live only 50 miles from Flowerw**d nursery, which is well known for their Enco** azaleas. I'm leaving a few letters out of the name to protect myself here, but I'm sure most of you know who I'm talking about. I once went on a job interview there and the place is huge, I can't remember how many acres. I can tell you it IS all about the money. Some of the plants they grow are okay, but about half of them are garbage in my opinion. None of the employees are aware of the invasive issue, most of them don't speak english. They do what they are told to get a paycheck. I can't tell you how many acres of ligustrum and nandina I saw, among others. I never took the job they offered, but thinking back now I don't know if I could live with myself peddling some of that garbage to the public.

The Bradford Pear cultivar was deemed a "Solution Cultivar" long before this buzz phrase came into existence. We are just now beginning to see the long term consequences the introduction this "Solution Cultivar" has had-
http://www.agnr.umd.edu/ipmnet/5-8art1.htm

Although this article is somewhat dated, he was the first to notice that the Bradford Pear cultivar wasn't exactly "sterile" in the presence of all the other "Solution Cultivars" of Pyrus calleryana that were created, marketed, and sold to the unsuspecting public by the boatloads. Much research is out there on the invasivelness of P. calleryana now and volunteers in natural areas are being trained on how to identify it so that they can remove it from the landscape while nurseries are still selling it from sea to shining sea because of its popularity. I personally don't think we can take any more "Solution Cultivars".

Bob Stewart just sent me a copy of the original interview with the "Father" of the Bradford Pear a few weeks ago. Gee, that original interview seemed to show up everywhere in archives for everyone to read a few years and now it seems you just can't locate it online anywhere??? Try to find that original interview on line anywhere, it has disappeared into the black hole of cyber space. Hmmmm??? Needless to say the "Father" of the Bradford Pear was very emotional and sorry he had ever unleashed the Bradford Pear on the land and he went to great pains to explain why.