Ruby-throated Hummingbirds Return

Every spring I look forward to the return of the Ruby-throated Hummingbird from its usual winter range in Central America and Mexico. Many congregate on the Yucatan Peninsula, using it as the jumping off point for a 500 mile, eighteen hour, non-stop flight across the Gulf of Mexico. Hoping to ride a tailwind, some instead meet adverse winds and use up their small energy supply of stored fat before they reach our coast and fall into the Gulf. For those that make it, it is an amazing feat of endurance and navigation. The first arrivals in our area show up around March 15th.

Ruby-throated Hummingbirds breed in the eastern United States from the Gulf coast of Texas, almost due north through Minnesota, into southern Canada and eastward from Lake Okeechobee to Nova Scotia. Many of the hummingbirds you see in your yard are passing through on their way to their breeding grounds farther north. Some will stop in north Florida to find mates and raise young. After mating, the female goes to her preferred nesting habitat, often near a woodland stream, river or swamp. She builds the nest and raises the two babies with no help from the male.

After hatching, the young stay in the nest about three weeks. Mom feeds them by ramming a regurgitated mixture of insects down their throats. For this reason, native trees and shrubs are very important to the survival of hummers. These plants are preferred by native insects that hummers consume by the thousands. Insects provide all the protein, vitamins, minerals and fats hummers need for a balanced diet and are critical for feeding the baby hummingbirds. These insects are found almost exclusively on American native plants. Ornamental plants from other parts of the world, such as camellias, loropetalum, azaleas, ligustrum, crape myrtle or Chinese elm are mostly useless for providing hummingbirds with insects.

The best way to attract hummers is to plant a wide variety of nectar producing plants. Try to use natives like red buckeye, wild azaleas, coral honeysuckle, firebush, columbine, red swamp mallow and silverbell. Non-natives like pentas, perennial salvias, shrimp plant and cardinal guard are good choices also.

Feeders are another way to attract hummingbirds. Use only white sugar. Mix with water at a ratio of four parts water to one part sugar, or one cup of water to ¼ cup sugar. Commercial nectar mixtures containing added vitamin, protein or flavors are not recommended. Red food coloring is not necessary and may be harmful. Never use honey since it carries a fungus that is fatal to hummers.

By mid-July, northern hummers are already migrating south, mostly males at first. From April through September, the bird visiting your feeder, the bird you call ‘your hummer’, is probably a different bird every day. Fred Dietrich, a certified hummingbird bander, caught seventy-two birds in his yard during this period. Only three of them were recaptures. The latest you’ll see a Ruby-throated Hummingbird in your yard is around mid-October. They have probably doubled their weight for fuel to make the dangerous Gulf crossing.

We never fail to be amazed by these feisty little animals. Imagine the spunk, courage and drive it would take for us to leave dry land and fly five hundred miles non-stop over water without a GPS, a phone to call for help or any food and water. Amazing!

Blueberries are Pollinated by Native Bees

In the last few weeks of March last year I watched some very busy bees visiting flowers of the native highbush blueberry bush planted just outside my home office window. They also visited the hybrid rabbiteye blueberry bushes in our yard and at the nursery. They look and sound like bumble bees, except they are smaller and faster. These are Southeastern blueberry bees, native to the southeastern U. S., and they forage primarily on blueberries. What amazes me is that they are active only for a short period of time each year, which coincides with blueberry flowering of mid March into April in our area. Blueberry flowers are visited by honey bees, bumble bees, carpenter bees and the southeastern blueberry bee. Carpenter bees are nectar robbers. They are able to make a small slit at the base of the flower to rob nectar without brushing against the pollen structures. For this reason, they are not good pollinators of blueberries. The non-native honey bee commonly uses the holes made by carpenter bees.

Blueberry flowers contain a male part called an anther that is tubular in shape with an opening at one end from which the pollen is dispersed. The blueberry bee attaches to the flower and vibrates her flight muscles very rapidly which causes the anther to work like a salt shaker, shaking pollen out of the opening. This is called buzz pollination. When the bee goes to the next flower, her vibrating flight muscles shake out pollen again and also causes the pollen clinging to her body to attach to the stigma, the female part of the flower. Thus pollination occurs, resulting in the eventual delicious blueberry fruit surrounding the seeds.

Honey bees are not able to buzz pollinate. Bumble bees can pollinate blueberry flowers successfully through buzz pollination but their numbers are comparatively low in early spring. They are, however, the major pollinators of tomato plants which also need buzz pollination.

So where and how do these blueberry bees live? They are solitary ground nesting bees. They dig burrows in sandy or loose soil. Sometimes they burrow beneath hardwood forest leaf litter or in the walls of earthen holes, perhaps where a tree was uprooted exposing a hole and soft soil.

Ground nesting bees choose a bare, sunny spot that is not likely to flood. They dig a long tunnel slightly wider than their own bodies. They may do this by themselves or they may do it in the company of other bees of their own species. They are still solitary in that each bee digs her own nest and provisions her own brood. At the end of the tunnel, she builds a brood cell chamber for one baby, a larva. The mother bee fills the brood cell with enough pollen and nectar for one bee to grow from egg to adult. She lays an egg and seals the chamber .Then she may add branches to the tunnel where she provisions another cell at the end of each branch. Blueberry bees produce one generation per year and adults are active for only 3-5 weeks.

Solitary bees do not have colonies to defend, so would only sting if you accidentally crushed them. Don't be afraid to get up close to watch these blueberry bees moving quickly from flower to flower, gathering pollen.

There are three things you can do to encourage Southeastern blueberry bees. First plant their favorite plant, blueberry bushes! Second, avoid using pesticides. Blueberries are generally pest free and very easy to grow, but you also should not use lawn pesticides which could affect underground nesting bees. Finally, allow natural patches of exposed soil as part of the habitat in your yard; this could be an area of patchy lawn or mowed weeds. Loosen up a little and have a slightly wilder yard.

For more information about Southeastern blueberry bees and other native bees such as bumble bees and sweat bees, contact The Xerces Society for Invertebrate Conservation at www.xerces.org.

Senecio a/k/a Golden Ragwort

­­­­­­­If you’ve been noticing a lot of yellow, daisy-like flowers in shady gardens this last week or so, you’ve most likely been seeing Senecio a/k/a Golden Ragwort (Packera aurea). This native wildflower forms an evergreen, perennial groundcover in the right conditions. It’s often used in the sun up north, but our southern sun is too strong for it, so plant it in full to part shade here in the Tallahassee area. It likes moist soil, but also does well in normal garden conditions. For this reason, it’s a great choice for rain gardens. It’s also a good choice for attracting bees and makes a good cut flower, too! American Indians used the roots and foliage for a medicinal tea. The foliage is mildly toxic however, so we would not recommend you try it yourself. Senecio’s satiny, heart-shaped basal foliage grows to a height of eight inches. Its flower stems grow to two to three feet and produce clusters of golden-yellow flowers up to one inch in diameter. It spreads easily - by both root colonization and seed and will spread and fill in faster if you let it go to seed. It will also go through a messy stage if you do so. Plants expend a great deal of energy to create seed – energy taken from other processes such as foliar growth. For that reason, it will look a bit scruffy for a period of six to eight weeks after seed dispersal. I let it go to seed in my yard for the first few years after I planted it; but once it had formed a nice thick mass, I started cutting the flower stems at the base as soon as they were past their prime. If you do so, you will avoid that scruffy period.

Once it’s established, maintenance is easy. Keep Senecio watered during dry periods, and you may have to do a little pulling to keep it contained. That’s pretty much it, other than cutting those spent flower stems. The only pests that ever seem to bother it are leaf miners, but they are easy to control. When you see their tracks on the foliage, simply remove those leaves and throw them away. Leaf miners do lay eggs inside the leaf however, so be sure to throw them in the trash and not on the ground.

At Native Nurseries, we stock Senecio most of the year in quarts and 1-gallon pots. Currently we have quarts only. As always, give us a call to check availability before making a special trip (although we’re always happy to see you). Sorry . . . we do not ship plants.

Some information for this blog post came from the following sources –

http://www.wildflower.org/plants/result.php?id_plant=PAAU3

http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=l350