Coronilla varia, crown vetch, is a possibility.

Patrick Alexander

Thanks. I found it though. It's a type of Cleome. I think it's Cleome Spinosa.

It's not a native to PA. I wonder how it got here? :)

migrating birds?

Actually, I feel kind of embarassed. It is a Cleome Spinosa (Spider Plant) and I saw it in somebody's garden nearby as well. I also happened to see a couple in someone else's garden miles away.
Interestingly enough, I also found out that it is an alien that became a wildflower in Missouri(?) and it started out as a garden escapee. Looks like that is just starting to happen here too. ;)
Thanks to all who replied.
It smells very nice, kind of sagey. I wonder if it's had any herbal uses in the past? I think the leaves were once eaten as vegetables.

Aliens don't become wildflowers, they stay invasive exotics. Garden escapes have gone on to destroy many native ecosystems; we all need to be careful about what we have in our gardens - and keeping our plants there.

Pardon my ignorance. It was listed as a wildflower in one of the books I read. I can understand how you feel though. I lived in Hawaii for 3 years, and there were quite a few native animals(and I believe plants as well) who were made extinct or almost extinct from alien animals, insects, etc. Their laws as to what can come onto the islands now, as such as animals(no snakes allowed, for example) is very understandable.
However, I found out recently that this Cleome(ironically, a native of Hawaii) was born from seeds my one neighbor gave to my other neighbor(who lives right behind the mailbox), who gave them to her kids to plant in the yard, and they must have scattered the seeds there.
It's a beautiful flower, and it supposedly attracts hummingbirds, from what I have read. I've seen more in other people's gardens here and there, and I recently spotted a garden center selling them. I think they're annuals, so I really am not sure how much of a threat they could be.

"Wildflower" is a term not always used uniformly. My tendency would be to use it to only refer to native plants, but I think most people use it to refer to anything that's growing outside of cultivation. So... Cleome spinosa certainly isn't native, but whether that means it isn't a wildflower depends on which definition of "wildflower" you want to use.

Another thing to keep in mind is that some of the most damaging invasives are annuals. Garlic mustard is an excellent example. I don't know if Cleome spinosa is capable of becoming a threat in your area or not (I've never heard of Cleomes being particularly invasive, though), but the fact that it's an annual isn't a useful way of figuring out whether or not it can pose a threat.

Patrick Alexander

I found Cleome to be invasive in my garden in Florida, but I never found it in a natural setting. I planted one plant and then had to pull up its seedlings for the next two years until I got it under control. It is also grown as an ornamental here in Japan. I haven't seen it growing freely in the woods or roadsides however. PF

When I use the term invasive I'm referring to introduced species which spread rapidly and uncontrollably into natural areas and displace native vegetation. Cleome doesn't fit that description.
Environmental groups in various parts of the country publish lists of invasive species based on field data. Such lists are referenced on this forum all the time. They really are the best source of information as to what is a problem and what is not.
Sam