March blooming plants native to Pennsylvania, USA

I live in the NE, SE PA specifically, and on my property like many woodland gardens there are snowdrops and winter aconites blooming right now. They are the earliest plants that bloom on my very landscaped with some remaining (definitely not intact) woodland. It’s not surprising to see honeybees visiting these flowers, what does surprise me is finding Andrenas visiting these flowers as well.

I’ve been trying to restore the wooded areas of the property removing all of the invasive that escaped the landscaped areas, my plan is to also remove the snowdrops and winter aconites as they have spread freely everywhere, while the snowdrops has not formed dense colonies the winter aconites has.

My question is, (and thank you if you’ve read this far) are there March blooming native plants that these bees would’ve been visiting instead?
I’d hate to remove the snowdrops if they are actually providing food for the native bees.

I tried googling and the plants that came up don’t bloom until April/May.

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The way I would go about it is to look for existing iNaturalist observations, filtered for flowering plants, Pennsylvania, and March:
https://www.inaturalist.org/observations?month=3&place_id=42&taxon_id=47125
I did this using the existing filters; with a bit more URL savvy, it would be possible also to filter for the “flowers” annotation.

It’s not very encouraging: those linked results have lots of winter aconite and lots of snowdrops, as well as quite a few crocuses.

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I’m just a little south of you (DMV), and right now, yeah, it’s a lot of non-native spring flowers (snowdrops, crocuses, daffodils, squills, lesser celandine), which seem to come up a bit earlier than the native stuff.

The two that I think of as the earliest-blooming common natives around here are Virigina springbeauty (Claytonia virginica, which Andrena erigeniae, the spring beauty miner, is associated with) and spicebush (Lindera benzoin) (I guess skunk cabbage even earlier, but I don’t think that’s bee-pollinated). Some other native flower observations I have from the first half of last March are: Hepatica americana, Micranthes virginiensis, Cardamine concatenata, Erigenia bulbosa, Dicentra cucullaria, Sanguinaria canadensis, and Mertensia virginica.

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Try spring ephemerals!
https://www.inaturalist.org/projects/spring-ephemerals-of-the-northeastern-united-states-and-canada

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Thank you! I have many of those, bloodroot grows wild here but it doesn’t bloom until late March at least from my records of it. My hepatica doesn’t bloom until April :upside_down_face: I planted both round leaf and sharp lobed.
I did just plant a bunch of mertensia virginica, but they were bare roots so it might be a while before I see those bloom.
Skunk cabbage is pollinated by flies and beetles.
I will look into adding some cardamine concatenata and erigenia bulbosa. Thanks again!

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I do have quite a few that I’ve planted and some that grow wild. Thanks!

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How about trees? I can’t recall the specific ones that bloom in March. Perhaps willows? But those are more catkinny…

Pussytoes!

You can set the filters to your region and the observation month “march” (or any other): https://www.inaturalist.org/observations?month=3&place_id=42&subview=table&iconic_taxa=Plantae

Scroll through the pictures, it seems that there is not too much flowering.

Crocus, Scilla, Hepatica, Galanthus, Tussilago…?

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I like this site for finding native plants. They have lots of filters, and a range map for each one. With filters for PA and March bloom, there is only one that they have, Pussywillows.

https://www.prairienursery.com/pussy-willow-salix-discolor.html

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Thanks!

Some willows are nevertheless insect pollinated. Scouler’s willow is one I know on the west coast, but I don’t know the willow flora in Pennsylvania.

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If I did this right, this link has plants annotated as flowering in March in PA and excludes species marked as introduced:

https://www.inaturalist.org/observations?month=3&native&place_id=42&quality_grade=research&subview=map&taxon_id=47125&term_id=12&term_value_id=13&view=species

Narrowing it down to a county (or counties) might help narrow down plant choices. Flowers will bloom earlier in Southeastern PA than in Northwestern PA.

Thanks everyone!! I’ll be keeping the snowdrops for now and focus on adding more spring ephemerals.

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Some thoughts from the perspective of bee life cycles and flower relationships. I’m in central Europe, but I imagine most of these points also hold true for the northeastern US.

Except for social species like Bombus and some of the halictids, most wild bees are proterandrous, meaning that the males (like the Andrena in your photo) appear a week or two before the females. What this means is that for these really early bees, nectar is probably more important than pollen – sustenance for a hungry newly emerged or overwintered bee rather than provisions for offspring.

Bees that collect pollen only from a small range of plants are not bound to the hosts plants for nectar in the same way.

One of the bee specialists here writes that Galanthus is not a particularly good source of nectar; this fits with my own observations, which is that the bees here don’t seem particularly interested in snowdrops even when these are much more plentiful than other options. Scilla and Muscari, by contrast, are very well received – I would be more concerned about removing these than Galanthus. Eranthis is happily visited but around here it seems to be just about over most years when the solitary bees are starting to emerge, so it is only useful for a fairly short period.

I’m not very familiar with what native species might be good candidates in Pennsylvania. Using phenology annotations on iNat is likely to only provide a very incomplete picture because so many observations are not annotated. You might try looking at observations of bees in March/early April and seeing what they are visiting, though this may give you a lot of non-natives.

Salix is fairly important here as a nectar and pollen source for many of the spring bee species. Some other plant families that include relevant early-blooming species are:
Allium, Asparagaceae
Berberis
Asteraceae
Brassicaceae (preferably large-flowered species)
Lamiaceae
Rosaceae
Boraginaceae
Campanulaceae
Caprifoliaceae (Lonicera, Symphoricarpos)
Cornus
Ericaceae
Fabaceae
Veronica
Primula
Ranunculaceae
Viola

I’ve been pondering similar questions about what I can put on my balcony this early in the year. We had several really warm days last weekend and as a result the bees have started emerging, but there isn’t a lot that is blooming yet. While native plants would obviously be preferable to introduced ones, I think there are some arguments for flexibility, particularly when climate change and weird weather may be upsetting previous phenology patterns (with the potential that bees and flowers might not be completely in sync).

Many of the bees that I’m seeing are also urban bees – meaning that they are those that have adapted to the conditions of cities, which in many cases may offer more plentiful flowers (parks and cemeteries and even garden centers) than they would otherwise normally find this time of year.

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Another thing that occurs to me is that unusually early Andrenas may be stylopized – that is, hosts of an endoparasite, usually visible in a small bump protruding between the segments of the abdomen. (I don’t see this in your photo, and it is more common in females than males, but we don’t see enough of the abdomen to rule out the possibility.)

Stylopized bees are sterile, so in such a case a scarcity of food sources, while of course unfortunate for the bee in question, is not going to have larger ramifications for the survival of the local population of that species.

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This topic has inspired me to be more attentive to bee-flower relationships this March, so thank you! Last week I noticed many native ground-nesting bees hovering around a flowering red maple, which I had assumed was wind-pollinated, but, according to the USDA NRCS,

Because of the abundance and wide distribution [of] red maple, its early-produced pollen may be important to the biology of bees and other pollen-dependent insects. Most references describe red maple as wind pollinated, but insect pollination may be important, as many insects, especially bees, visit the flowers.

Red maple is one of the earliest-blooming common trees in my neck of the woods (along with American elm and boxelder, but I haven’t noticed any bees around those so far).

I’ve also seen quite a few native bees around the spicebushes that are blooming now. Plus a week ago I too spotted a (very sluggish) Andrena on a snowdrop, which I probably would not have seen had I not been looking.

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Very interesting! I’ll have to be on the lookout for that. Thanks!

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When does American holly flower in PA? Right now in NC, the introduced Chinese holly is popular with carpenter bees.