Æsculus parviflora, new growth

For April, we are featuring an under-used performer for the shrub border or high-canopied shady areas, the bottlebrush buckeye, Æsculus parviflora.  One of eight species of buckeye native to North America, it occupies a relatively small native range from the Savannah River west across central Georgia and Alabama and south to the Florida panhandle, but easily adapts to cooler climates as far north as Chicago and Portland, Maine.

Æsculus parviflora, leaf detail

In its native mid-south, Æ. parviflora form dense stands along bluffs and ravines and in high-shaded forests.  Typically maturing at 8 to 12 feet in height, it tends to slowly spread laterally by suckering so that a single individual may cover 25 feet in width at maturity. In the landscape, the coarse texture and smooth light grey bark make an excellent backdrop for smaller shrubs and perennials.   Like most buckeyes, leaves emerge from large buds relatively late in the season; the large, palmate leaves with 5 to 7 leaflets usually provide a dense dark-green cover to the shrub from the ground up.  The showy white flowers, peppered with red anthers, are produced in cylindrical bottlebrush-like spires up to a foot long in early summer when few other plants are in flower. The foliage usually turns a clear butter yellow in early autumn.  Unlike in its native range, Æ. parviflora rarely sets fruit in the landscape.

Æsculus parviflora, flowers

As a landscape plant, bottlebrush buckeye is low-maintenance.  Pruning is rarely required and although suckering, the shrub spreads slowly so that unwanted new shoots can be easily removed.  It has no significant pests, although it can suffer from leaf scorch in prolonged periods of hot, dry weather.  It prefers a moist, well-drained soil in full sun, but is also very tolerant of light shade and can perform well in drier situations if regularly watered for the first few years while becoming established.

Æsculus parviflora, flowers

Like their closest relatives, the maples (Acer); buckeyes contain saponins in their leaves and fruit.  Saponins are defensive compounds that impart a bitter taste thus discouraging browsing.  They are also especially toxic to cold-blooded vertebrates; native Americans used the ground buckeye fruits and other saponin-containing plants to stun fish in ponds and other stagnant bodies of water.  Buckeye fruits (so-called because they are shiny brown with a yellowish attachment scar, much like a deer’s eye) were also commonly used in tanning leather.

White House Natives supplies Æsculus parviflora in sizes from 3 ft to 6 ft.   It is a deserving native that can be a welcome addition to the shrub border.

Pinus virginiana, 8 ft, at the nursery.

February’s Featured Native is Pinus virginiana.  Commonly called Virginia or scrub pine (or Jersey pine in a certain state to our northeast), Pinus virginiana has been a long-ignored native evergreen that has in recent years become more prominent in the naturalized landscape.   With a native range spanning the East Coast from Long Island to the Chesapeake, then southwestward through the Blue Ridge and Great Smokies to the Cumberland Plateau, it is an adaptable and fast-growing species.   Along with P. rigida, the pitch pine, it is a primary species of the well-known Pine Barrens ecological area of southern New Jersey.

In its native range, P. virginiana tends to grow in almost pure stands, usually maturing at 30-60 ft in height.   In the landscape under more ideal conditions, it can grow taller; up to 75 ft.   The largest recorded specimen topped out at 105 ft.  Broadly pyramidal in youth, it tends to grow more contorted with age, developing a broad, flat-topped, irregular, and ragged crown that serves as an interesting focal point in the landscape.   The orange, brown and cinnamon-colored bark and short, sharp, paired needles often lead to confusion with Pinus sylvestris (Scots pine), a poorly-adapted species which was extensively used in the landscape in the first half of the 20th century.   It can be distinguished by its yellow-green, twisted needles and 2½” ovoid cones, compared to the flat, blue-green needles and short, squat cones of P. sylvestris.  Unlike most pines, the cones of Virginia pine develop over two seasons.  The female flowers emerge in the spring and are fertilized by the bright yellow pollen-bearing strobili the following spring, then mature in the autumn.  Cones are produced every year, with some individuals bearing a heavier crop every third year; they can persist on the tree for up to fifteen years.  In good growing situations, the tree can grow to 18 ft in its first ten years and bear cones at five years of age.  Virginia pine is

Pinus virginiana, male flower detail.

especially useful in the landscape due to its tolerance for a variety of soil conditions; while it prefers a well-drained sandy or loamy soil, it can also thrive in drier, rockier soils, albeit with a slower growth rate and is relatively drought-tolerant compared to most evergreens.

Virtually all parts of the tree were used by native Cherokee peoples; tonics from the needles and bark for ailments such as bowel problems, fevers, and tuberculosis, tea from needles steeped in apple juice as a tonic, root tonic as a stimulant, pine tar as a waterproofing agent, and branches in burial rituals.  European settlers found the wood useful for poles and ship masts as unlike most pine, the wood becomes harder and stiffer as it dries due to crystallization of the high pitch content.  Today, P. virginiana is often grown as a Christmas tree and is an important and renewable source of wood pulp for paper-making.

Mature Pinus virginiana in the wild.

In the landscape, Virginia pine is useful as a backdrop to a shrub border, as a provider of high, light shade for annuals and perennials easily scorched by direct sunlight or as a picturesque specimen.  It can be affected by the fungal pathogens Porodaedalea pini and Fusarium moniliforme and insects such as pine beetles and sawflies.   All of these are relatively uncommon in the landscape and can be mitigated by good cultural practices.

White House Natives supplies Pinus virginiana in sizes from 5 ft to 8 ft.  It is a unique and interesting native that deserves a spot in the larger garden.