Hoary alyssum
(Berteroa incana)

Description:
Stems - Multiple from the base, erect to ascending, herbaceous, mostly unbranched (except at apex), to 1m tall, scabrous from dense forked and stellate pubescence.in 2001.

Leaves - Alternate, sessile. Blades linear-elliptic, entire, 5-8cm long, +/-1cm broad, rounded to subacute at apex, stellate pubescent above and below, reduced upward on stem.

Inflorescence - Terminal and lateral racemes to +/-25cm long. Racemes dense in flower, quickly elongating in fruit. Pedicels ascending, to 7-8mm long, stellate and forked pubescent.

Flowers - Petals 4, 5-7mm long, deeply notched at apex, tapering at base, glabrous. Lobes rounded to acute at apex. Stamens 6, erect, glabrous, white, 3-4mm long. Anthers yellow, to 1mm long. Ovary superior, green, densely stellate pubescent, 1mm long in flower. Style green, to 2mm long, sparse stellate pubescent, persistent in fruit. Sepals 4, erect, densely stellate pubescent externally, glabrous internally, 3-4mm long, to 1mm broad, with scarious margins, elliptic, acute. Silicle 6-7mm long, elliptic-ovate to orbicular, stellate pubescent, beaked, with 6-10 seeds. Beak to 2mm long.

Other info. - The plant is very common in more northern states and is spreading throughout much of eastern North America. The plant is easy to ID in the field because of its deeply divided white petals and gray stellate pubescence.

• Mechanical: Not Known
• Biological: Fertilizers and soil fertility management have been used to effectively control hawkweeds in some areas, especially in new hawkweed infestations or where hawkweed density is relatively low.
• Herbicide: Herbicides are effective in suppressing hawkweeds but reinvasion occurs unless other plant species fill the gaps left by hawkweed removal.

For More Information:
Detailed information about noxious weeds is available at the Washington State Noxious Weed Control Board Web Site.