Contents tagged with autumn
Created: 10/8/2014 Updated: 8/8/2016
(Do you need an introductory paragraph? No. No you do not. So I’m not writing one. If you’re unsure about what subject matter you will encounter in the following paragraphs, please reread the title. Thank you for your understanding. This really saves me a ton of work.)
Foliar FlaggingSumac exhibiting foliar flagging
You remember how you were taught in school that chlorophyll masks the other pigments present in leaves, and that when chlorophyll production stops in the fall, these pigments become visible? Of course you do, because you loved science, which makes you wholly superior to those mouth-breathers who’ve forgotten all about leaf pigmentation. But did you ever stop to wonder what those other pigments are doing in the leaves in the first place? Well, it turns out they might be doing lots of things. Like murder. Or something more benign, but equally fascinating, like foliar flagging.
Let’s say you’re a sumac tree. You want birds to eat your berries, because they will then fly away, pooping out your progeny hither and yon like tiny, gross little Johnny Appleseeds. So you make your berries bright red and obvious to hungry birds. But birds are kind of dumb, so why stop with the berries? Why not turn your leaves a similar color, so even the most dim-witted and unobservant avian can’t help but notice you and your pretty berries, free for the munching? Turns out a number of trees and shrubs use this strategy – certain dogwoods and Virginia creeper to name a couple.
Conifers That Didn’t Get the MemoDawn Redwood
Ever have one of those dreams where you show up to school naked and everyone else is fully clothed? And then your substitute teacher shows up, except it’s Henry Kissinger in a clown costume, and he announces that he’s your real father? No? Just the first part, you say… Huh… Anyway, if you’re a Dawn Redwood, a Larch, a Tamarack, a Bald Cypress, or a Chinese Swamp Cypress, (or a Ginkgo, if you wanna be inclusive) you live out that archetypal Freudian quagmire every fall. All the other conifers are standing there fully clothed in green needles, while yours are falling away, one by one, until there you are all starkers, just in time for the coldest part of the year. Why? Aren’t there good reasons why needle-leaved plants are typically evergreen? Yes, but look at the big picture. There are advantages to having needle-shaped leaves: they retain water better, they’re less attractive to insects, and they take fewer nutrients to produce than broad leaves. And there are advantages to being deciduous: it avoids problems with freezing and over-drying in winter, reduces herbivory, and prevents breakage from snow and wind. So it’s not too surprising that some trees can make the seemingly contradictory “deciduous conifer” lifestyle work for them.
Free Stuff You Can EatYew berries
Autumn is not just about pretty colors, falling leaves, and the sudden appearance of pumpkin spice everything. The fruits of many plants also mature at this time of year, making it the perfect time for nature snacking. Those aforementioned sumac berries, for example, make a nice tea. (You’ll want to sweeten it. It’s sour from malic acid, the same stuff that’s in a sour apple.) Or try some hackberries – they’re ripe when they’re smooth and dark brown. If you value your teeth, don’t bite down hard; just chew off the outer coating. You’ll see why they’re also called sugarberries.
If you’re feeling really adventurous, try a yew berry, but DO NOT EAT THE SEED INSIDE!! It’s poisonous. I’m serious about this, guys. Deadly. Freakin’. Poisonous. However, the flesh of the red ‘berry’ (not really a berry, but that’s a subject for a different blog post) is sweet, non-toxic, and sort of gelatinous. To be safe, squeeze the seed out, throw it away, and lick the fruity goop off your fingers. You’ll be glad you dared yourself to try it.
Created: 11/27/2012 Updated: 8/10/2016
The simple answer is, baby squirrels don't leave the nest until they are fully furred and can survive on their own so, without seeing the mother right next to the babies, they all look about the same size.
Most babies leave the nest in April or May. At this point the babies are fluffy and fat but the parents have exhausted their winter fat and are beginning to shed their winter fur, so look relatively small. A second litter of babies may leave the nest around September. At this point the parents have begun putting on fat and winter fur, so the apparent size difference can be greater. Because of this, it may be easier to identify babies born late in the year.
Although baby squirrels have been recorded in almost every month of the year, these two litters, early spring and late summer, are the norm. Typically the early spring babies have the highest survival rate, especially in areas where it snows, since a small squirrel has to expend more energy than a large one to stay warm and find food.
I managed to take a few pictures of a baby and a young adult male that were foraging near each other in the same park. Unfortunately, tree squirrels aren’t very social so I couldn’t get any useful pictures of them near each other, but they found my pen interesting so there is some scale. The pen is about 16cm long.
A baby grey squirrel.
An adult grey squirrel from the same population as the baby in the previous photograph.
Another view of the adult. Note the more “mature” features.
Even with the specimens in-hand, assessing age can be somewhat qualitative but when the babies are very young, they are simply more cute than the rest of the population.
If you're a squirrel watcher, like me, I hope you take the time to record your observations at projectsquirrel.org . Your data, combined with that of others around the country, helps us understand more about squirrels and about the nature in your neighborhood!
Created: 11/20/2012 Updated: 8/10/2016
Chicago is a birding hotspot especially in spring and fall during migration. The Chicago Ornithological Society lead morning bird walks around North Pond every Wednesday which start and finish here at the Museum. The list of species they have observed right outside our windows is very impressive. We are always looking for new ideas for public and school programs so a few years ago when the idea of a bird watching program was suggested we installed some bird feeders at the north east corner of the building.View Comments
Even we couldn’t have imagined just how successful they would be. We have recorded the first ever sighting for Lincoln Park of a Yellow-headed Blackbird and when an extremely unusual Cinnamon Teal blew in one winter it too paid a visit to our feeders.
Last winter we had a regular Red-headed Woodpecker adding a splash of colour outside our window.
And this spring we were inundated with Baltimore Oriole’s draining the nectar from the hummingbird feeders.
Now fall migration is upon us again and the Red-breasted Nuthatches are making the most of the peanut feeder.
And of course there is always that endearing year round favourite, the Downy Woodpecker.
Depending on the time of year we have a constant parade of colourful species so next time you are at the Museum be sure to visit the North Terrace, you never know what you might see.
Created: 11/15/2012 Updated: 8/10/2016
Autumn in New York
Why does it seem so inviting?
Billie Holliday sang the praises of fall in the Big Apple, and if a recent weekend was any indication, it would be hard to disagree (though some might this year, thanks to hurricane Sandy.) There is something agreeably evocative about brownstone stoops strewn with cast off foliage and planetree leaves chattering down the sidewalk on a fresh breeze. On the way to JFK after a weekend with family, I took a detour to Brooklyn Botanic Garden to revel in the sunshine and autumn color, and while the grounds had sadly suffered a number of tree falls from the storm, it was nonetheless a lovely afternoon.
The Garden was quiet and felt particularly dignified, perhaps due to the somber hues of drying leaves and the lack of energetic floral activity. However, one stop on my circuit of the Plant Families Garden sent me into fits of decidedly indecorous laughter. A grand, gnarled old tree – perhaps the largest and oldest on the grounds, and a species I was previously unfamiliar with – was earnestly labeled with its scientific name, Pterocarya fraxinifolia, and its common name, Caucasian Wingnut.
While “Caucasian Wingnut” is a label some might choose to apply broadly, it seems a bit unfair to condemn an entire species to derogatory snickers and finger pointing. But at least the CWs, as I will mercifully abbreviate them, have plenty of company. Many a plant has endured a lifetime of awkward introductions at cocktail parties. Pity the poor Mountain Misery, Midnight Horror Tree, Beggar’s Tick, Corpse Flower, Mal Mujer, Crybaby Tree, Lousewort, Fly Poison, or Pleuro amparoana, also known as the Toilet Bowl Orchid.
Deservedly or not, other species have fared quite well in the name game, such as Balm of Gilead, Fairy Petticoats, Sorrowless Tree, Enchanter’s Nightshade, Venus’ Looking Glass, Kiss Me Over the Garden Gate, and a favorite here on the Museum's grounds, the Rattlesnake Master. Euphorbia leucocephala has it particularly good. Its many common names include Snows of Kilimanjaro, Christ Child, and Little Christmas Flower. Other plants must get a lot of confused stares from doormen and receptionists: Ramping Fumitory, Moses in a Boat, Napoleon’s Hat, Monkey Puzzle, and Rat Stripper to name a few.
There are scientific names – always Latinized – that take the cake in both lyricism and absurdity. Consider the poetic qualities of words such as Dasylirion, Mandragora, Bauhinia, Ipheon, and Vitex agnus castus, which translates to “chaste lamb of life.” Dread the doubtless horrors of Dracula nosferatu and Monstera deliciosa. Or, try some lingual calisthenics with a couple of cactus species, Weberbauerocereus cephalomacrostibas and Austrocephalocereus dolichospermatichus. Quiz tomorrow. Spelling counts.
But back to New York and our dear CW. No matter how ridiculous its name, the tree I visited that afternoon was remarkable – venerable, steadfast, antediluvian. Perhaps we should thank Sandy for sparing it, but then, the tree has surely stood strong in the face of many storms. And perhaps, with maturity, it’s learned to laugh at its awkward moniker and even appreciate the chuckles of passersby. They say laughter is the secret to long life. Maybe this Wingnut is living proof.
Created: 10/8/2012 Updated: 8/10/2016
The last, tremulous notes of the ice cream truck have faded into the distance. Sales of fun-sized candy bars are spiking. And all across this great nation, people are attaching their egos to teams of large, colorfully outfitted men battling over oblong balls. Yes, fall is here, and leaves are raining to the ground like opponents’ home runs onto the bleachers of Wrigley Field. But why? Why would otherwise perfectly reasonable trees decide to shamelessly expose their naked limbs? (In front of the saplings, no less!)
Thanks, guys. You know I'm gonna have to rake that, right?
Well, winter is hard on us all. For plants, the main problem is water, which, like most people, becomes sedentary and expands during cold weather. Sedentary water (by which I mean ice and snow) can’t be absorbed by a plant’s roots. So when the ground is frozen, water lost through its leaves can’t be replaced. Most plants in our area avoid the problem by stripping bare.
As for expansion, water is quite odd in that it becomes less dense when it freezes, so the same amount of water takes up more space when it becomes ice. This is a big deal for plants, since it causes their cells to quite literally explode as the water inside them swells. Try freezing a salad and you’ll know what I mean.
So instead of risking death by dehydration or cell destruction, a clever tree ditches its leaves for the winter. But, you say, ever the contrarian, what about evergreens? Well, your average pine or spruce has small leaves with thick 'skin' to slow water loss. And it's quite industrious, churning out resins and antifreeze compounds to prevent cell damage. Deciduous (leaf-losing) trees can't be bothered to spend as much energy on such nonsense. What antifreeze they do get around to manufacturing is concentrated in their buds in preparation for spring.
All this hard work gives evergreens a competitive advantage in early spring, when temperatures are warm enough for efficient photosynthesis. Deciduous trees can’t get moving until they stop hitting the snooze button and get to work cranking out leaves, while Joe Spruce is already soaking up the vernal sun and adding inches. The tables turn in summer, when the larger leaves of deciduous trees allow them to collect more light and grow faster than our work-a-day friend Mr. Spruce. These differing strategies are one reason evergreens dominate the landscape of northern latitudes. Short summers don’t allow those deciduous layabouts enough time to catch up.
Seth Harper - Museum HorticulturistView Comments