Identifying features of Dame's Rocket vs Annual Honesty

Lunaria annua and Hesperis matronalis look fairly similar from a distance or bad photo (common in the unidentified tag), and they can both be found in my area. Any tips? Or should I just default to Brassicaceae since they’re both in that family

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To me, it’s the leaves. Annual honesty has big, heart-shaped leaves with the base much wider than the tip. Dame’s rocket has more lanceolate leaves and a hairy stem

Also, the seed pod shapes are different, if the plants are flowering. For annual honesty, the fruit is coin-shaped (a silicle). For dame’s rocket, its a cylindrical (a silique, like what you would see on garlic mustard or yellow rocket)

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Besides the most important features already mentioned (leaves and seed pod shape), there are also some rather subtle differences regarding the flowers: Hesperis matronalis usually has more and longer hairs on the calyx and the center of the flowers is greenish in contrast to the more or less white center of Lunaria annua.

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I have a hard time with this, too. If it’s a high-quality observation, then no problem, but people often take photos of it from a distance so you can’t see the leaves or petals too well. I have occasionally identified distant pink clouds on the roadside as Dame’s Rocket, as it just seems to be the more likely choice by a huge margin. I have seen thousands of them scattering the countryside but only a few isolated examples of Lunaria.
Especially this seems to be the case when there is pink and white mixed - although there is a white Lunaria out there, I haven’t seen it outside of an intentional planting. However, maybe I should be more conservative? or perhaps geography might be more of an issue - maybe Lunaria is more common in places outside of PA?

The previous owner of my yard planted purple Lunaria, and it volunteered that way for years, until a few years ago it became mixed and the white proportion is substantial by now!

Yes and I think we can find a very few cases… but should that prevent us from identifying what is more statistically likely? For instance, in PA there are 3200 observations of Hesperis matronalis and only about 250 of Lunaria annua, and a very small number of these are white. It seems like a stretch to not ID something just because there less than a percentage of possibility that it is another thing.

I’m also having that issue with bog spicebush and southern spicebush. I can’t ID them, but I often ID Northern spicebush. I try to stay out of the few counties or perhaps even states where the former two occur, but should I quit Id-ing Northern spicebush anywhere near these areas just because there is a slim margin of possibility I might be confusing it for a very rare plant?

I frequently see disagreeing IDs (as in bumped back to genus) with comments suggesting that people are doing just that.

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Yeah, and I see their point, but if the main objective is to help engage the community with their natural environment and not be 100% accurate, which we will fail at anyways, I think they will be more engaged with a species than a genus or family. Again, there’s a fraction of a percent chance that your average person will actually encounter bog spicebush. You have to really be looking for it. You could say it is just as likely that something is growing outside of it’s natural range, but people use ranges for ID all the time.

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