Sweet Pea (Lathyrus latifoliu) is finishing up a very colorful summer in disturbed areas and roadsides of the area this summer.
Two late summer blooms are putting on good shows in South Lewis and Northern Cowlitz County and both are purple/blue blooms.
One native species is Fireweed (Epilobium augustifolium) while the other is Sweet Pea (Lathyrus latifoliu,) which is an invasive immigrant from Eastern and Southern Europe and even calls Northern Africa home. While it is defined as invasive, it is not listed on the State of Washington's Noxious Weed list.
The flowers of Sweet Pea are pollinated by bumblebees. Butterflies occasionally suck nectar from the flowers, but they are not effective at pollination.
The plant includes showy flowers, which are currently very visual but can reproduce vegetatively from its taproot and rhizomes, or by reseeding. It usually forms large patches that out-compete most native competition and dominate up to several hundred square feet of disturbed ground.