Verbascum blattaria Identification

Verbascum blattaria Identification - Summer 2016

Verbascum blattaria over 4 feet tall.

I observed a tall flower stalked plant with unusual but showy flowers. I sent a picture mentioning I was having difficulty identifying the species and my friend found its image online. Through this image, I then confirmed with Gleason and Cronquist’s Manual (2014) and the Illustrated companion (Holmgren 1998).

Flowers of Verbascum blattaria

I found the white form, but the flowers can also be yellow. The flowers have a purple center. The dimorphic stamens (male parts) of the flower are said to resemble a moth, thus called Moth Mullein (http://www.ct-botanical-society.org/Plants/view/665). The plant is invasive to the United States, native to Eurasia (both Europe and Asia), and declared a noxious weed for Colorado (http://plants.usda.gov/java/noxious?rptType=State&statefips=08). It is found in disturbed areas (http://www.illinoiswildflowers.info/weeds/plants/moth_mullein.htm) such as roadsides where I found the plant. It can be found growing from June-October (Gleason and Cronquist 2014). I will also credit Wikipedia for aid to citations (https://en.wikipedia.org/wiki/Verbascum_blattaria).

Leaves and form of Verbascum blattaria.

A Professor collected seeds of 23 plants (2 trees and 21 herbs). The herb seeds were mixed with sand, placed into a bottle, and buried. The bottle was left open, but positioned facing down to prevent the collection of water. Beside the bottles the nuts/acorns were buried. This was done around 1879 with 20 bottles. Years later the bottles and nuts were unearthed and examined for germination (would the seeds grow). The nuts decomposed early in the years. At first every 5 years a bottle was taken. Then every 10. Then in 1990 it was decided every 20 years. In 2000 the 120 year mark removed the 15^th bottle with seeds examined. Three of the herbs grew. Verbascum blattaria was among the seeds along with a hybrid. Verbascum blattaria has had the best results for long term survival with germination in this experiment. Interesting the seeds of this plant has the potential to last over 120 years! (Kivilaan and Bandurski 1981; Telewski and Zeevaart 2002).

Seed capsules and seeds of Verbascum blattaria.

Verbascum is the anciet latin name for the plant. Blattaria refers to the Latin name for cockroach, blatta. This plant has been noted to repel cockroaches (http://www.oardc.ohio-state.edu/weedguide/single_weed.php?id=79). I am skeptical.

End of the season for this Verbascum blattaria plant. Same plant pictured at star of this post.

Identification (skip if not interested in technical jargon):

To key the plant in Gleason and Cronquist (2014) I went straight to Dicotyledons, has perfect flowers (both male and female parts), with a perianth (has both calyx [sepals] and corolla [petals]), superior ovary (I cheated and looked this up because I didn’t look at time of flowering for superior or inferior sometimes a challenge for me). The perianth has a sepal and petal whorl, or more than one cycle perianth. Flowers are gamopetalous (petals are united to form a tube), and stamens (male parts) as many as lobes of the corolla (petals). This takes me to section 17. From this section key, this isn’t covered by glands as in Droseraceae, leaves aren’t bipinnately compound, stamens alternate with lobes of the corolla (petals). Ovary not lobed, and ovary 2-4 locular, not 3 locular. Style with 1-2 stigmas, or each bode with 1 stigma (kind of confusing), leaves alternate, fruit a capsule with many seeds and finally the corolla rotate or saucer-shaped, some filaments hairy; flowers in terminal racemes, spikes or panicle. This gets to Scrophulariaceae with parenthesis Verbascum. The genus of this plant. At the Scrophulariaceae description: has perfect (stamens [male] and carpels [female]) flowers. The petals are usually connected with 4-5 lobed calyx (sepals) and 5 lobed corolla (petals). Petals may be slightly irregular (not radial symmetry) and may be spurred. Stamens come from the corolla tube (stamens appear like they are growing from the petals) often 5 but usually 1 isn’t functional, rather dimorphic (two different types, perhaps by length) stamens (male parts), so you often see just 4; but with a note you can see 5 stamens all polliniferous in Verbascum. Also ovary superior (female part attached to a part beyond the sepals and petals). The synopsis of the subfamilies and tribes of Scrophulariaceae: upper lip of the corolla overlapping the lower lip in bud, with 1 stigma, with 5 anther-bearing stamens, takes us to tribe Verbasceae. The key to Scrophulariaceae: corolla without a spur or saccate gibbosity at base, foliage leaves alternate or all basal, stems erect, flowers larger, mostly 1-5 cm long or wide, stamens 5; corolla nearly regular. This gets us to Verbascum. At Verbascum the calyx (sepals) and other parts glandular-hairy (not smooth, hairy, and perhaps sticky) not branched hairs (hairs that are split if looked at through a hand lens), with corolla (petals) that are white or yellow. This leads to Verbascum blattaria.

 

Thank you for your interest. Have a Great day!

Gleason, H. A. and A. Cronquist (2014). Manual of vascular plants of Northeastern United States and Adjacent Canada. Bronx, NY, The New York Botanical Garden Press.

Holmgren, N. H. (1998). Illustrated companion to Gleason and Cronquist's manual Illustrations of the vascular plant of Northeastern United States and adjacent Canada, The New York Botanical Garden.

Kivilaan, A. and R. S. Bandurski (1981). "The one hundred-year period for Dr. Beal's seed viability experiment." American Journal of Botany 68(9): 1290-1292.

Telewski, F. W. and J. A. D. Zeevaart (2002). "The 120yr period for Dr. Beal's seed viability experiment." American Journal of Botany 89(8): 1285-1288.