Q. I recently heard a Kansas State University professor from Monarchwatch explain that no Monarchs showed for their festival in Canada this year. One major reason he cited was the eradication of milkweed plants on farms that grow genetically engineered crops, and so he is proposing that homeowners establish milkweed 'way stations' in their gardens. What do you think? I certainly plan to grow a lot of milkweed this year.
---Gracie in Chewelah, Washington
A.I knew there was a problem here, but a little research revealed that the situation is much more dire than I had thought, with some scientists speculating that the migration of monarchs across North America may become extinct within our lifetime.
One reason is that illegal logging in Mexico has reduced the amount of land they use for their winter home down to a small fraction of what it was. There are online petitions that people can sign urging intense protection for the remaining stands of trees.
And genetically engineered crops are the other reason. Although science promised us that these crops would reduce pesticide use, the opposite has been true. The most popular genetically engineered crops are the so-called "Roundup Ready" corn and soybeans from Monsanto. A staggering 90% of the corn and soybeans grown in the US are 'Roundup Ready', a genetic tinkering that allows farmers to saturate their fields with massive amounts of this potent herbicide—at levels that would cause 'normal' corn and soybean plants to wither up and die. Milkweed is only one of many 'wild' plants that have suffered collateral damage from this practice, but it's THE crucial plant for monarch survival.
Milkweed feeds monarch babies; it's their nursery, day care center and cafeteria all rolled up into one. When adult monarchs migrate up from Mexico, they're looking for milkweed plants to lay their eggs on. When the eggs hatch, the baby caterpillars feed on the plant. It is the only 'host' plant for these very special caterpillars. And so the hope is that home gardeners can replace at least some of the milkweed lost to Roundup. (Also a Monsanto product; what an amazing coincidence.)
As we've explained in previous Questions of the Week, there are several different types of milkweed that home gardeners can easily grow—from the basic "butterfly weed " (Asclepias tuberosa) to the "swamp milkweed" that can handle wet soils.
But longtime butterfly breeder and monarch champion Rick Mikula is among many experts urging people NOT to grow the more exotic, tropical varieties. There's a risk that they're harboring a disease that's deadly to monarchs, and they might interfere with migratory instincts. Just plant milkweeds that are native; that the monarchs recognize as belonging here.
Q. We also heard from Margaret who lives near Quincy, Illinois and listens to us on WQUB. She writes: "I have several milkweed plants come up as volunteers in my flower bed every year, and I'm happy to leave them for the monarchs....up to a point. They get very large and crowd out the other plants. Can I pull them AFTER they have served as lunch for the baby monarchs? Or do the caterpillars also make their chrysalises on milkweed? If so, I would obviously need to postpone pulling them even longer. Thank you for your advice."
A. The caterpillars need the plants to stay in place until the end of the season, when they will emerge as adults, feed heavily on pollen and nectar plants and then fly back to Mexico, hoping that there's still some trees left for them to live in when they get there. So either leave the milkweed in place all season or transplant it early in the season to a less crowded area of the garden—with careful thought as to their placement.
As both Rick Mikula and fellow butterfly enthusiast Ron Richael have stressed, you should place your milkweed as far away from birds as possible. Don't grow milkweed—or the pollen and nectar plants that the adults crave, like Mexican sunflower —near birdbaths, feeders or nesting boxes. Birds are one of the biggest predators of both the adult and caterpillar stage.
Now, let's talk a bit more about Mexican sunflower, whose scientific name is "Tithonia" ("Mr. I Don't Know Latin Names" remembers this one by mentally playing Shirley Ellis' "The Name Game" with Shakespeare's Fairy Queen from A Midsummer Night's Dream. Works every time. At least if you're dyslexic)...
Anyway, Mexican Sunflower isn't the only pollen and nectar plant that the adults look for. The organization "Monarch Watch" also lists coneflowers —Echinacea is the flower of the year for 2014, by the way—as well as Red Sage, which also attracts hummingbirds, Joe Pye weed, and zinnias .
…Although Ron feels strongly that Tithonia is the best fuel for the adults as they begin to make their long trip down South.
Tithonia or Mexican sunflower …whichever one you can find first.
Previous monarch Questions of the Week, citing lots of plants for hosting and pollen-providing:
Of Milkweed and Monarchs
Plants That Attract Butterflies
Great article about the habitat loss in Mexico.
A letter to President Obama and Mexican leaders proposing a unified solution to both the loss of milkweed caused by use of herbicides on genetically-engineered crop fields and the loss of overwintering habitat in Mexico, signed by an international cadre of hundreds of scientists, researchers and environmentalists.
Information on the Monarch Watch "Waystation" program .
Special thanks to butterfly breeder Rick Mikula for links, inspiration and information.