Can you handle the prickly truth about this traditional Christmas greenery?

As you deck the halls with boughs of holly this holiday season, here are a few tidbits you might not know about this prickly member of the Ilex family.

For instance, did you know that the name Ilex comes from its similarity to the leaves of the evergreen oak (Quercus ilex)?

Or that there are over 400 species of deciduous and evergreen shrubs, trees, and climbers, even some epiphytes - that comprise the holly line?

Did you also know that the traditional Christmas holly we know and love, English holly, grows prolifically in the Pacific Northwest but is not native to Oregon?

Christmas holly

There are over 200 cultivars of the English holly (Ilex aquifolia). This dense and pyramidal broadleaf evergreen shrub/tree gets up to 50 feet tall. It is favored for its glossy dark green leaves as well as red berries used in holiday decorating.

Popular this time of year is both the non-variegated (green-leaved) or variegated varieties. Variegations typically are yellow/gold margins or white/silver margins.

The Northwest Holly Growers Association (www.nwholly.org) lists 18 member farms that supply the vast majority of variegated and English holly to both wholesale and retail buyers throughout the country during the holiday season.

The use of holly as a symbolic winter decoration goes back to the Celtics who used it to decorat their homes during Yule. Ancient Romans believed holly keep lightning strikes and witches at bay. The early Christian Church used it to celebrate the birth of Christ. All three believed the prickly holly leaves were symbolic of the crown of thorns from the crucifixion and the red berries symbolic of the blood of Christ.

Holly is easily identified by the thorns that grow on the edge of the leaves (spiny-margins), but did you know that some species have leaves with smooth margins or even berries that are not only red, but yellow, white or black?

Although most holly is thought of as evergreen, Ilex verticillata "Winter Red" (Winterberry Holly) is a broadleaf deciduous shrub. It gets to 8 feet tall and wide with an upright rounding habit.

Battle of the sexes

Dioecious is my new favorite word. All hollies are dioecious, meaning male or female flowers grow on separate trees. However, only the female tree produce the coveted red berries.

Hollies have nondescript white fragrant flowers in spring - male and female on their respective trees. Bees must visit both male and female flowers during the same outing to achieve cross-pollination. Thus both sexes are needed for good fruit set.

Friend or foe

Unlike the English holly, our native American species prefers the humidity of the Southeast, growing bountifully in the Appalachian region, down to Florida and up along the Atlantic coast.

English holly, however, adapts to many types of soil - if well drained, and does well in either sun or part shade. Cool temperatures and plenty of rain typical of the Pacific Northwest are ideal habitat for it to thrive.

Thus, this native of Europe is becoming naturalized in Oregon, Washington and California. The seeds are easily distributed by birds. I noticed a lot of dried sprigs of English holly had been cut and were lying along the trails at Peavy Arboretum when I hiked there over Thanksgiving weekend.

According to Pat Breen, self-described CPN (Certified Plant Nerd) with the Department of Horticulture at Oregon State University, English holly is common there and also in the Finley Wildlife Refuge.

It is becoming a growing concern. Control, although not mandatory last I heard, is recommended in natural areas that are being restored to native vegetation and in protected forest lands.

Ilex virtue

Many cultivars have been developed from the English holly for use in landscaping. According to Breen, there are a large number of Ilex species and cultivars on the OSU campus.

"I would guess that the most popular campus species is Ilex crenata, the Japanese Holly. It is often used as a low hedge, especially the cultivar "Convexa." "Helleri" and "Green Island" are also rather common," Breen says.

He manages the popular OSU Landscape Plants website. Check it out at http://oregonstate.edu/dept/ldplants/2plants.htm - it's one of my favorite Internet sources.

Using their instructions as my guide, I was able to locate 7 types of Ilex in less than an hour. (A trip around campus would help you discover their virtues of Holly before buying any.)

* Ilex aquifolium -

English holly, both glossy green and variegated.

A great specimen of both variegated and non-variegated are across the service road from the northeast corner of Withycome Hall at OSU.

* Ilex cornuta "Burfordii"

Burford Chinese holly - has a single terminal or double lateral spines. North side of the parking lot north of Bates Hall.

* Ilex cornuta "Rotunda"

Rotunda Chinese holly - compact, dense and mounding. North side of OSU Foundation office near 35th and Western Blvd.

* Ilex crenata "Convexa"

- Convex Japanese holly - small convex leaves and black fruit. Found on the south and east sides of Cordley Hall.

* Ilex crenata "Helleri"

Heller Japanese holly - low-growing mounding, 2-4 teeth on each side. Located north side of parking lot (along Orchard Ave.) north of East Greenhouse.

* Ilex x meserveae -

Meserve Hybrid holly - Blue Hollies have trademark dark stems. Selection "Blue Princess" and pollinizer "Blue Prince" east side of West Dining Hall.

PS. Did you know that the Oregon grape holly (Mahonia aquifolium) is neither a grape nor a holly but a member of the barberry family?