Friday, March 6, 2015

Mixed emotions

Text and Photos by Fred Heath

The Sweet Resin Bush (Euryops multifidus) is a beautiful member of the Sunflower Family which brightens up the winter in Sabino Canyon with its lush green foliage and bright yellow flowers. There is one huge problem though: Euryops is a very invasive plant from South Africa.

Photo by Fred Heath 2/2/2015

From a purely selfish viewpoint, it makes it easy for me to find butterflies, because it is an attractive nectar source when there are not many native plants providing nectar at this time of year (January/February). The plant comes from South Africa and thus thinks it is summertime. 

Great Purple Hairstreak (female) on Euryops 2/5/2015

Mallow Scrub-Hairstreak on Euryops 2/5/2015

My wife Mary and I have recorded 39 species of butterflies this year so far in Sabino Canyon. Of these, 17 species have used Euryops as a nectar plant. (See two examples, above)

Assassin Bug on Euryops 2/14/2015

The Assassin Bug (above), an ambush predator, knows to wait for the many insects that come to nectar on Euryops.

In the long run, though, Euryops won’t be good for butterflies. They can use many different plants to get the sugary nectar that gives them energy to fly around searching for mates, but most butterflies are particular about which hosts (plants the caterpillars eat) they use. Some will only use (i.e., lay eggs on) one species of plant, and others use only plants in one family. Thus, if a nectar plant is gone, it might be a little harder for butterflies to find nectar, but if the host plants are gone, the butterfly can’t produce offspring. If the invasive Euryops crowds out the native plants such as the mustards, there will be no Sara Orangetip and other whites. If it outcompetes the Desert Senna, there goes the Sleepy Orange and Cloudless Sulphur. No Fairydusters would mean no Spring Azures, and a lack of Daleas would mean no Reakirt’s Blue and Southern Dogface. This is why, with mixed emotions, I will do the right thing for the butterflies and help remove the Euryops from Sabino Canyon.

Anne says: Debbie, Jerry, Fred, and I removed 5 heavy-duty bags of Euryops on 2/26 as part of the Sabino Stewards (volunteering with the Forest Service). Alas, there's plenty more. If you are interested in helping with the ongoing (volunteer) efforts against invasives in Sabino Canyon, send me an email and I'll put you in touch with the movers and shakers (and the pullers and sprayers). 
Never ever go rogue and pull or damage any plant in Sabino Canyon.

No comments:

Post a Comment