Hello friends –
Work has been a little hectic and Its been a few weeks since I have posted my last blog. Inspiration struck the other day when I had posted a picture of my globe thistle (Echinops sp.) in flower on a Facebook page. Someone posted that it was pretty but it was not native. Yes, globe thistle is native to Eastern Europe and Asia. However, this got me thinking what is a native plant? Where do we draw the line in the sand when we determine if a plant is native or introduced?
Some of the earliest settlers to northern portions of North America are thought to be the Clovis people who used natural passageways from Siberia to Alaska some 11,500 years ago according to a paper published in the journal Science in February of 2007. The paper mentioned that prehistoric people hunted mastodon. Now did they bring plants with them? Eleven-thousand years is a long time to allow any introduced plants undergo speciation. Would those plants be considered native? What about Columbus in 1493 or the Jamestown colony in 1607. What seeds or plant material did they bring with them and did those plants escape cultivation? We know that white clover did – a non-native perennial weed in lawns but highly prized for its nutrient content for pollinators and ability to fix nitrogen in the soil. Bluegrass is another non-native perennial that is extensively used. Where are those boundaries when we define native and introduced and what to keep or get rid of?
So what is a native plant? Lois Berg Stack with University of Maine Extension defines native plants as those plants that originated here or arrived here without human intervention. It is simple but straight to the point answer.
This brings me back to the globe thistle. We needed a plant that could take the hot southwest sun and grow in rocky soil. It would not get any water and very little from rain. We wanted a plant that would benefit pollinators and need little intervention from us. Globe thistle fit the bill. I am sure there would have been other plants such as coneflower, goldenrod, ironweed, rattle snake master but we opted for the globe thistle. Does this make it a poor choice? There is no right or wrong answer and it will ultimately have to align with our paradigm. Most urban and prairie urban locations do not have an ounce of native soils. The soil where the globe thistle was planted is highly altered and littered with landscape rock. You could barely put a trowel in the ground without hitting rock. Globe thistle are known to thrive in dry, shallow rocky soils. Would it have been better to plant a recognized native plant that may not thrive in those conditions? Following the right plant right place principle would lead you to believe that no is the answer.
We know that introduced plants can out compete native plants and take on characteristics that make them a weed. After all kudzu was purposefully introduced to help with soil erosion, create shade and some even suggest as cattle fodder. We all know how that turned out. Kudzu has been nicknamed the vine that ate the south. But should all introduced plants be frowned upon? Like I said earlier, no easy answer and we need to seek balance with native and introduced. After all I don’t want to have to give up my tomatoes (origins in South America) or my peonies.