Our native Magnolias

I had planned to go into much greater detail about Magnolias this spring, but found myself a bit caught off guard by our strange weather, which seemed to cause spring to not only come quick, but to also progress at a much faster rate than I would have anticipated. Most of our native Magnolias however flower in late spring or early summer, so were a bit protected from this. I'm probably not going to do a big entry like this for a while as gathering all the pictures I need takes quite a bit of time, but for now, we'll continue with one of my favorite genera, Magnolia.

Southern Magnolia (Magnolia grandiflora)

The Southern Magnolia (Magnolia grandiflora) is probably what would come to most people's mind when thinking of a native member of the genus. During my time living in New England I can only think of two or three which I saw growing at all, both in heavily protected locations and one of which had a noticeable yellow hue to the foliage throughout the winter months. It's for this reason I was a bit surprised to see the species flowering last week here in Delaware. Even though I'm now living in the range where these can be grown quite a bit more easily, I had still envisioned them as a species which flowered a bit later in the summer. Apparently, this is not the case. Still, it is an interesting plant not only for the large, white flowers, but also for its thick, leathery, evergreen foliage which on some plants has a heavy, brown pubescence to the underside. One of the hardiest cultivars, 'Bracken's Brown Beauty', has such a heavy pubescence the undersides of the leaves appear a dark brown in color, and is probably one of the best choices for those feeling courageous and wanting to grow the species in New England (I've also seen 'Edith Bogue' performing quite well).

Sweetbay Magnolia (Magnolia virginiana)

Up in New England, its much more common to see the Sweetbay Magnolia (Magnolia virginiana) in the landscape, though there is one wild population known in Massachusetts. It's considered to be "Semi-evergreen", as many leaves will often remain on the plant through the winter months. I've seen this vary immensely from tree to tree. The vast majority of plants I witnessed in New England would have few if any leaves present on the tree by February, probably 5% leaf cover at maximum, though there was one plant in Boston I remember being surprised to still have something like 75% cover even after a cold winter. When I moved to Delaware, as expected many of the trees held more leaves, and though the winter here was very mild this year, one plant seemed to still have nearly 90% leaf cover in the coldest week of January.
The flowers are quite nice as well, and though they are noticeably a bit smaller than that of the other Magnolias I'm describing here, they do tend to bloom for a longer period of time as far as I can tell. I've heard of their fragrance being described as somewhat lemony.

Cucumbertree (Magnolia acuminata)

The Cucumbertree is different from the above two species first as it is fully deciduous and thus holds no foliage over the winter months, and second, is one of only a few magnolias which is not considered to have a particularly showy flower. Personally, I find it to be quite interesting even if admittedly less attractive due to the waxy appearance and greyish, maybe blue-green color to the outside of the petals (defintley more green in the photo above). I'll actually often refer to it as my favorite Magnolia in order to be a contrarian, which is probably not much of a surprise to anyone who knows me personally. Anyway, the Cucumbertree is also quite important in Magnolia breeding as it is the source of the yellow color found in the flowers of many magnolia hybrids, such as 'Elizabeth', 'Butterflies', and 'Yellow Bird'. The name Cucumbertree is in reference to the fruit, an aggregate of multiple follicles which resembles a cucumber, especially before it has fully ripened. Other Magnolias also have an aggregate fruit, but it generally tends to resemble a cone-like structure, often seen on the ground with several red follicles emerging from the black rotting "cone".

Umbrella Magnolia (Magnolia tripetala)

Auriculate leaf base of Magnolia fraseri

And for comparison, Magnolia tripetala,
which lacks this base

The next two species, the Umbrella Magnolia (Magnolia tripetala) and the Fraser Magnolia (Magnolia fraseri) are very similar species and are often confused in the trade, but can be reliably distinguished from each other so long as you know what you're looking for. The base of the leaf blade of the Fraser Magnolia is auriculate, meaning it has two earlobe-like projections which extend towards the petiole (the stalk holding the leaf blade). The leaf of the Umbrella Magnolia has no such projections, instead narrowing to a point on either side of the blade. Both these trees flower quite nicely, with the Fraser Magnolia often having a flower which stands upright for a long period of time, whereas the Umbrella Magnolia has a flower which many find to have a rather disagreeable fragrance.

The Bigleaf Magnolia (Magnolia macrophylla) is a deciduous tree fairly similar to the above two species, but distinct enough that I credit it as being the tree that got me interested in botany and horticulture. When first seeing the plant, with its large undulating leaves spanning almost the entire length of my arm, as well as the huge flower buds that would soon open to reveal proportionally huge flowers, I found myself almost instantly questioning and challenging my perceptions on what a tree was. I'd always had a bit of an interest in plants, trees in particular, but it wasn't I saw this one that I really made it a point to learn more. I'd soon realize there was a lot more to plants than "the green things that don't move", and gain an appreciation for biodiversity which would alter my career and educational plans from that point on. Embarrassingly enough, I actually don't have all that many photos of it to share. I do however have a nice closeup of the closely related species Magnolia ashei (Ashe Magnolia), which is very similar though has a distinct purple blush towards the base of the tepals which the Bigleaf Magnolia lacks. The Ashe Magnolia is also interestingly endemic to (only found within) the Florida Panhandle, though it grows quite well when planted as far north as Boston.

Ashe's Magnolia (Magnolia ashei)

On a personal note, I'm finding myself wrapping up my first year of graduate school and still really enjoying the experience. I'm heading deep into doing my thesis research over the summer which looks to involve quite a bit of time in the library as well as some lab work, but I plan to still find some time to wander out into the gardens as well and hopefully get some photos of a few more plants that pique my interest.

A few native pines

Though spring is rapidly approaching, with snowdrops and some of the earliest daffodils and crocuses already appearing (as well as flowering cherries and magnolias in some places), the canopy still looks noticeable sparse as our deciduous trees have yet to show signs of leafing out, the only green up high provided by either broadleaf evergreens such as the American Holly (Ilex opaca), or the needles of conifers such as the pines.

The evergreen nature, as well as their distinct needles make members of the Pine Family (Pinaceae) one of the easiest groups of trees for the less botanically inclined to identify: Pines have needles, other trees have leaves. The strength of this distinction holds well in plant taxonomy, as it is actually made at the phylum (or division) level, which as you remember is the second category after kingdom: this is indicative of the fact that Conifers and deciduous trees took a different evolutionary path quite a long time ago, with deciduous trees and other flowering plants or angiosperms branching off from the conifers sometime in the Cretaceous Period 65,000,000 to 145,000,000 years ago.

Regardless, needles are considered to be the leaves of the pine: they photosynthesize and have similar anatomy, they're simply round instead of flat, and have a tendency to stay on the tree for more than one year (2-5 is probably a good range). They also usually have a thick waxy cuticle that leaves of most deciduous trees lack.

Pines are distinguished from their relatives such as Spruces, Firs, and Hemlocks in that they have needles borne on the stem of a plant in groups of two or more in a structure called a fascicle, as opposed to being borne singly.

Small grove of Eastern White Pines (Pinus strobus) at the University of Delaware

Cone of Pinus strobus

The Eastern White Pine (Pinus strobus) can easily be distinguished from the other pines listed here as they have five needles per fascicle as opposed to two or three. The needles are also a good deal thinner, less prickly to the touch, and give the tree in general a much softer appearance, even when viewed from a distance. The tree usually reaches a height of 50-80 feet in height, and can also grow quite quickly, sometimes upwards of two feet a year. It is unfortunately very intolerant of pollution, making it quite difficult to grow in urban settings.

Pinus palustris (Longelaf Pine)

Longleaf Pine (Pinus palustris) is a more southern species, and quite easily identifiable due to the sheer length of its needles: they can approach upwards of a foot. There are some other pines which get as long or even longer, but in tropical, not temperate areas. The terminal bud on the stem is also a good ID characteristic, being large and white, though probably unnecessary given how distinct the leaves are.

The growth habit of Longleaf Pine is also somewhat interesting: for the first seven years of its life, it looks more or less like a grass, barely reaching a foot in height. It is however in the process of developing a root system, and once established, it rapidly increases in height, usually getting to about 60' but in some cases well over 100'. This growth habit actually makes the Longleaf Pine an undesirable plant for foresters, as the amount of time it spends in the "grass stage" makes it rather economically nonviable in terms of wood production.

Close up of the needles of Pinus palustris. Almost wish I had my hand in the frame for size comparison, but regardless, you'll know this species when you see it.

And in colder weather...

The next three pines are a bit less distinct: Pitch Pine (Pinus rigida), Pond Pine (Pinus serotina), and Loblolly Pine (Pinus taeda) all have either two or three needles per fascicle (usually three).  If you're in New England however, you're unlikely to see the latter two species as they don't really start appearing in the wild until you get to New Jersey and points south.

A young Pitch Pine (Pinus rigida) at my parents' house in West Tisbury, MA

Pinus rigida as a bonsai, seen
at the Philadelphia Flower Show

Pitch Pine (Pinus rigida) was one of the first trees I learned how to identify. When at summer camp one year (I cant remember if it or Sassafras came first), I remember the counselor talking about the three needles per bundle (I doubt the term "fascicle" was used), saying we could remember that since in baseball they throw pitches, and three strikes is an out. The only other pines I remember seeing on the Vineyard were Red Pine (Pinus resinosa) which only has two needles per fascicle, and Eastern White Pine (Pinus strobus), which as we already know has five, though maybe there were a few other two-needle pines as well. I'll have to ask about it next time I'm down there (well, actually "up" there now that I've moved to Delaware).

Pitch Pine is quite ubiquitous on the vineyard, especially around my parents house right now as most of the oaks have died following repeated attacks by the Forest Tent Caterpillar. opw the Pitch Pines have the sun they need and are rapidly taking over the property. I'm all for it personally but haven't been able to convince my dad to let them live: they're one of his most hated trees, and probably justifiably so as I seem to recall him needing to cut a rather mature specimen down right next to the house which had its own established Yellow Jacket population associated with it. Still, though the species is probably not the most ornamental of pines, it does do quite well in poor soils so it at leasts has its place in the wild.

Loblolly Pine (Pinus taeda)

Loblolly Pine (Pinus taeda) resembles Pitch Pine to a certain extent, though it does have a tendency to get a bit taller (upwards of 90' where Pitch Pine usually, but not always, maxes out around 60'), and as noted about Loblolly Pine isn't generally found in the wild up north. Most notably however, the needles of Loblolly Pine are a bit longer: between 6-10" as opposed to Pitch Pine's 3-5".

What Loblolly Pine really resembles, in both range and needle length is Pond Pine (Pinus serotina). There are two easy ways to tell them apart however. First, the cones of Loblolly Pine are quite a bit longer and more extended. Since cones are not always present however, you can also look at the terminal bud on the stem. In Pond Pine, the bud will be white and covered in resin, whereas in Loblolly Pine, it is not and is red in color.

The word "Loblolly", according to dictionary.com anyway, apparently refers to a mud pit with the consistency of porridge. Who knew?

Shorter and rounder cones of Pond Pine (Pinus serotina)

Longer cones of Loblolly Pine (Pinus taeda)

White, resin covered bud of Pond Pine (Pinus serotina)

Redder terminal bud of Loblolly Pine (Pinus taeda), you want to look at the structure on
the end of the stem: try not to be distracted by the developing male cones underneath.

Pond Pine (Pinus serotina)

Not much more to say about Pond Pine (Pinus serotina). It's a close relative of Pitch Pine with a more southern range. It also tends to inhabit a wetter habitat, as it's common name would suggest, generally found in areas with wet, poorly drained soils. Such as in the proximity of pines.

Out of the five pines discussed here, only one of them, Eastern White Pine, is really popular as a landscape plant. Though Pitch, Pond, and Loblolly Pine probably aren't the most ornamental and interesting of trees, I find it surprising that Longleaf Pine isn't more popular due to the needle length. I suspect that the same production issues which bar it from use in timber production may be to blame, with nurserymen perhaps unwilling to dedicate greenhouse space to a plant which won't be of a decent size until almost seven years. Still, I think it's a neat pine I'll be keeping an eye out for in the future.


Not really sure what to talk about next... waiting on some of the Maple and Oak ID posts until I can get some leaf photos. I want to talk a little bit about algae but need to read up on that first, but I do have a few photos of trees with interesting bark it might be fun to discuss as well...

the birch

I was planning on writing a bit on Nandina domestica (Heavenly Bamboo), but the shots I took quickly on Sunday aren't quite up to the quality I'm holding myself to so I think I need to spend a little more time on that first.

However, did take some other photos over the weekend while preparing for a lab on native trees I'm teaching this semester. Though I took these more to emphasize easy identification characteristics instead of the ornamental appeal of the plant, I still think it's a good excuse to talk a little bit about one group of our native trees: the birches.

Paper Birch (Betula papyrifera)
Note the cluster of three male catkins on the end of the branch

The Paper Birch is probably the first one that comes to mind when I think of a birch tree. It's actually one of the first trees I remember being interested in as a kid. Growing up on the Vineyard I was used to seeing Black Oaks, White Oaks, Pitch Pine, Sassafras, the occasional Red Maple, and that was about it. I saw one while up in Maine one summer, and remembered being confused over how different it was than any tree I'd seen before, with the thin, papery white bark smooth and cool to the touch. Maybe still as a result of this, like many birches, I'd probably claim the bark is the most significant feature of this tree.

So if that's the case then why did I relegate it to the background in the above photo? I didn't even widen the depth of field enough to bring it remotely into focus. Well, I was trying to highlight a group of catkins (essentially clusters of petal-less flowers), as they serve as a good characteristic to distinguish it from a similar species, the Gray Birch.

Grey Birch (Betula populifolia)
With a solitary male catkin

The name Grey Birch typically refers to the bark of this species, which is evident in the photo above mostly because of the lighting. If you see these plants out in the woods together though, sometimes both the Paper Birch and Grey Birch will have sort of an off-white color to the bark making them hard to tell apart. However, on this tree the male catkins tend to be solitary, instead of clustered as in the Paper Birch.

Yellow Birch (Betula alleghaniensis)

You might also see female catkins on birches, which are a bit stouter, and generally not on the tips of the branches. If you're in doubt over whether you have a male or female catkin, try rubbing it back and forth with your fingers. The female catkins will break apart rather easily while the males won't. And of course, there are male and female catkins on this tree as there are independent male and female flowers.

Now for the next three I actually do have the bark in full focus. First up is the Yellow Birch, or Betula alleghaniensis. The botanical name of this changed at some point, so you may see Betula lutea in reference to this species. The name lutea refers to the yellow, or golden lustre to the bark of this species. Now "yellow" probably isn't the first thing that comes to mind when looking at this tree, but once you think to look for it, there is a bit of a dark golden tinge to the bark, interrupted by the pattern of thick, obvious lenticels - pores of the tree used for gas exchange.

Were you to actually scratch the thin layer of bark open, you'd pick up on a familiar somewhat sweet odor: Oil of Wintergreen. The odor will not be quite so strong however as it would be for the Sweet Birch (Betula lenta)

Sweet Birch (Betula lenta)

The Sweet Birch is a similar looking tree to that of the Yellow Birch, but lacks that golden coloration. The Oil of Wintergreen it produces serves as a flavoring agent in Birch Beer. I've never been a huge soda aficionado, so I had actually never tried this (well, or at least don't remember it) until a few years ago. It was OK. I had the Polar brand (Worcester's finest), so I'm not sure if that was the best direction to go. I'd say this tree is a little less ornamental than the other one's I've listed here, but has actually become rather important in New England ecologically speaking as it's starting to take over the forests traditionally inhabited by Eastern Hemlock, which are dying off due to the threat of Hemlock Wooly Adelgid.

River Birch (Betula nigra)

Finally, we have the River Birch, which can be readily identified by the reddish-tan colored bark, peeling off the plant with enough of a fervor to leave bare spots on the trunk. I'd say this is one of the more common birches cultivated in the landscape. For my friends in Boston, there's an aspiring grove of these about halfway down the Greenway (Somewhere between the Aquarium and the Intercontinental). They do put on a nice show in the fall when the leaves turn a brilliant yellow. I did find those trees a bit difficult to work with as I seemed to be constantly having to prune the lower branches, as well as water the trees heavily in the dead of summer, also proving difficult as the trees were planted on raised grass mounds which the water tended to roll off of. As the common name suggests, River Birches do like their water, and seeing the fall color show in mid-July can be a bit disconcerting.

Though I didn't explicit mention it throughout the article, I hope you're gaining a bit of an appreciation for some of the sight recognition tricks someone like me would use to quickly identify a birch tree while in the field. If I see a tree that I can identify as probably being a birch, to figure out which birch is a matter of asking myself a few questions: Is the bark peeling heavily? Do the twigs have a sweet soda-like smell when scratched? If so does the bark look golden? And if the bark is white, thin, and papery, how many male catkins does it display?

Next time you think you see a birch out in the woods try asking yourself the above and see what you come up with. Especially since you can't use the LeafSnap app since it's winter (though at 50 degrees again today I'm still not convinced).