Are you good with Lupine sp. ?
Last year, and this year I practiced using the Jepson eFlora key to Lupinus. I identified several annuals and learned the main difference to confirm between L. nanus, and L. bicolor is the proportion of the banner petal. There are others on the key with a similar banner to L. bicolor, but I didn't expect to see them in the area I was looking, so I could safely ignore those.
Between L. nanus and L. bicolor the keel margin cilia are about the same. In L. nanus the banner is about as wide as long, or slightly wider than long. In L. bicolor the banner is longer than wide. Sometimes it is obvious. Once you get to know the local population, it is clear, as well.
L. nanus are generally larger, more densely packed whorls, and very fragrant in my experience. They also form large groups of plants. L. bicolor is usually smaller, and less dense. There are some other annuals in the branch of the key that L. bicolor is in, so you also check for a tooth on the keel. But I think the species in that group are not around San Luis Obispo County, if I recall correctly.
All this to say, if I look through all the observations of L. bicolor, I easily find many I'm sure are L. nanus to my eyes. People confirm their ID, and others jump on, but then they can't always explain why they made the choice. I think they're just looking at photos.
Then, north of here (San Mateo County, and north), apparently the banner on L. bicolor can look less narrow than smaller ones I've seen further south. At least from what I see people posting, and they assure me it is L. bicolor, but I can't tell by their photo.
Let's all please be more careful with these because they look so similar.
Thoughts?
