Sunday, September 29, 2013

Number 12

The number twelve is what pops into my mind when I think of hawthorns (Crataegus spp.). Is it because there are 12 species of hawthorn in Georgia? No, there are actually 53 species of Crataegus native to Georgia according to the USDA database, although a reference created for Georgia lists only 36 of “widespread occurrence”.  Twelve is the location of hawthorn on the list of top 20 woody plants in support of Lepidoptera in the mid-Atlantic region. Oak is number one, cherry is number two and after that all I can remember is hawthorn is number 12.

Spring flower, Crataegus uniflora

Hawthorn is a lovely small tree in general and deserves increased usage for more reasons than being number 12. Crisp white flowers in the spring make some of the species good alternatives to overused spring-flowering trees like ornamental pears (which are not native). 

Crataegus viridis ‘Winter King’

The cultivar Crataegus viridis ‘Winter King’ is a commonly available choice that grows up to 30 feet tall. A good display of flowers turns into a spectacular fall fruit show. It is also considered both drought and urban tolerant once established.

It is true that hawthorns do have thorns. Some plants have large thorns while others have more modest ones. Once trees reach a certain height, however, the thorns are not much of an issue to the average passerby. Hawthorns are sun loving plants and will flower and fruit best when sited for 6 or more hours of sun. I have several species native to my property and only those in sun produce flowers. 

Fall fruit, Crataegus triflora
As with any plant that has such a wide variety of species, there are species adapted to both dry and wet conditions. The coastal species Crataegus aestivalis, known for its fruit being made into mayhaw jelly, is naturally found in wet areas. Crataegus uniflora was the first hawthorn I ever noticed. It grows well in the dry woodland edges on my property. Handsome leaves frame white flowers that yield to small fruits in the late summer.

Washington hawthorn, C. phaenopyrum
Other popular landscape hawthorns include parsley hawthorn (C. marshallii) and Washington hawthorn (C. phaenopyrum). Parsley hawthorn has delicately shaped leaves and naturally grows in moist areas but does fine in average garden conditions. Washington hawthorn has small glossy fruits in abundance. 

Atypical fall leaves
of parsley hawthorn (C. marshallii)

C. spathulata

Little hip hawthorn (C. spathulata) is another species that is both attractive and adaptable.

If fruit size is important, look for downy hawthorn, C. mollis, or mayhaw, C. aestivalis. Fall color is not especially noted for hawthorns, although both Washington hawthorn, C. phaenopyrum,  and Crataegus viridis ‘Winter King’ are indicated as having reliable color.

Whether you want spring flowers, fall fruit, a plant to deter burglars, or just like having a plant that supports over 150 different Lepidoptera, hawthorn is well worth considering.

Fall fruit, C. munda

Reference: The 2006 edition of Tipularia, the Journal of the Georgia Botanical Society, features a thorough treatment of the hawthorns found in Georgia and includes a key and pictures of most species. Older copies of Tipularia may be obtained by contacting the editor.

Sunday, September 22, 2013

What You Don’t See Still Exists

Pretty obvious statement, I know, but a reminder doesn’t hurt. This has been a very discouraging year for some wildlife, particularly insects such as monarch butterflies and bees. Even more discouraging is that the ramifications extend beyond this year.  Lower insect populations mean lower bird populations in the future. Birds whose populations were already low may reach critically low levels, levels that make it hard to keep breeding. 

Chestnut-sided warbler

Last week I happened to look out my window at just the right moment to see an unusual bird flitting through the bushes nearby. I snapped a quick picture through the window screen. Not a good picture, but it was enough for me to identify that it was a hooded warbler. He had a few companions with him and I got a better picture of one of them. It appears to be an immature chestnut-sided warbler.

As the birds searched for (and found) a few insects to eat, I was glad that my plants had a few caterpillars on them. I was glad I had not used any pesticides. My friend JoAnn said that warblers come through in the morning this time of year as they migrate. They stop and rest for a while and refuel on insects (warblers are insectivores). I have seen small birds in the tops of trees some mornings – they always move quickly, as if searching, and chatter amongst themselves.

If I hadn’t seen these by my window at just that moment (they were quickly gone) then I never would have known that they come through. Or that they exist.

Trichostema dichotomum

Other things are overlooked. Tiny blue curls (Trichostema dichotomum), blooming now, are hardly noticed. Should they go extinct, would we notice? The species exists for a reason – we know that it supports native bees for example. 

Chamaecrista fasciculata

More people notice the colorful partridge pea (Chamaecrista fasciculata). It is considered a weed by most despite its cheerful yellow blossoms. 

It is a host plant for sulphur butterflies such as this pale cloudless sulphur that gracefully floats through the late summer garden. I had a lot of them last year so I’m glad that someone let their weeds live.

Cloudless sulphur (Phoebis sennae)

I went out to walk the dog for the night and a small grey moth flew away from the plant I brushed past. Without that encounter I would not have known it existed. Yet it and many other species of similar moths do exist and they play a role in our ecosystem. 

Perhaps one like it laid the egg that became this caterpillar now munching on the Conoclinium coelestinum. Perhaps this caterpillar will be the one to give tomorrow’s visiting warbler the energy to go a little further towards its winter home. I likely will not even see the encounter. But it doesn’t make it any less real.

Conoclinium coelestinum

Tadpoles are swimming in a bucket that holds water from our heavy summer rains. I can watch mosquitos lay their eggs (while their friends bite me). You probably think mosquitoes are useless, but they are actually the perfect size meal for hummingbirds and an important source of protein for them.  I hope the tadpoles are eating some of the larvae in the water, helping the frogs reach adulthood. It's part of the process.

The natural world around us is complex, but each piece carefully intersects with another. It’s good to remember that because our stewardship is important. So that even though we don't see them ... they will still be there.