Wednesday, April 3, 2013

native hawthorns

with carmine-raspberry anthers, parsley hawthorn (Crataegus marshallii)
is perhaps the prettiest bloomer of all native hawthorns

The Rose family is impressively large, holding about 2,000 species comprising at least 100 genera worldwide. Of course the rose genus (Rosa) is the first that comes to mind, but the Roseaceae holds many others including the blackberries, peaches, pears, plums, cherries, and apples.

Most amazing of all the Rose family genera is Crataegus, the genus of the hawthorns. Hawthorns are small wiry-stemmed trees. Besides thorns (mostly on new-growth only) most Crataegus species possess smooth pale bark, fine white blooms in spring, a dizzying array of leaf shapes, and bear small, red, apple-like fruits. Most of the Crataegus species come from North America, indicating our continent as the primary evolutionary progenetor and epicenter of the group. There may be fewer Crataegus species in Asia, but Asians nonetheless love their hawthorns, using both the candied-fruits and foliage as heart medicine -- still quite popular today.

the barberry hawthorn (Crataegus berberifolia)
is a personal favorite.......

The whacky thing about the hawthorns lies in attempting to organize the members of the genus into discrete, distinct species. Hard to imagine! I mean, taxonomists have pretty comfortably named most all the plant and animal species in the world by now. But not all of the Crataegus, by golly. In their Manual of the Vascular Plants of Texas – which is an excellent botanical reference that includes most all of the species in Louisiana – authors Correll & Johnston mention “There are close to 1,000 specific proposals that have been made in this [Crataegus] . . . genus,” meaning that in many many cases no one is really sure about what individual groups or populations of hawthorns to call a species.

this hawthorn was on our property when we bought it......despite showing
it to a few professional louisiana field botanists, it remains unidentified.....

There said to be a lot of hanky-panky going on within the genus, as hybrids between known species are many. Moreover, there is rumor about that Crataegus hosts more than a few species capable – if I understand it right – of producing viable seed without the aid of fertilization. Within the genus Crataegus, this is sort of akin to hybridizing with one's self! As all of us fruit-growers out there know: it generally takes two (or more) of the abovementioned fruit trees for best fruiting to occur.

parsley haw foliage and fruits
(photo by Annette Parker)

Here in Louisiana, as late as 1998, botanists Dale Thomas and Charles Allen (Atlas of the Vascular Plants of Louisiana) counted up 13 hawthorn species for our state; perhaps the most widely-known of which is Mayhaw (Crataegus opaca/aestivalis), one of the few hawthorn species to produce fruit in spring. Most all other hawthorns produce fruit in fall.

depending on genetic strain, mayhaw fruits run between
dime and quarter-sized........

Birds, mammals, and some humans alike love hawthorn fruits. Of course, here in the South we love our mayhaw jelly just as dearly if not moreso than we do our muscadine grape (Vitis rotundifolia) jellly. And with good reason: where else are you gonna get something that's naturally sweet and sour, possessing a wonderful rose fragrance to boot?

Hawthorn blooms are outrageously fine, possessing tissue-thin white petals and numerous variably-colored anthers. Some species bloom singly, others in clusters. All bloom in spring.

mayhaw blooms

green hawthorn (Crataegus viridis; aka "hog haw") is a fairly common
bottomland forest edge occurs natively on our property

Small size tree, soil adaptable, gorgeous blooms, good fruit = great candidate for the garden, ya'll. The down side is native hawthorns are tough to find in nurseries. Don't be fooled by “Indian Hawthorn” (Raphiolepis indica), the Chinese native that most nurseries carry. Best bet is to wait on seasonal plant sales held by local arboretums, botanical gardens, master gardeners, etc. Several such sales occur throughout Louisiana each year during spring and fall.