Trees that turn red


Foliage of the black tupelo tree, Nyssa sylvatica. We live in the northernmost part of native range of this beautiful and stately tree.

The underlying color of foliage is yellow–leaves begin yellow and turn green when they begin to produce chlorophyll. So why do some trees go to the trouble of turning fiery red in fall?

There are several theories. Some woody plants, vines in particular, turn red to signal to birds that their berries are ripe (birds have excellent color vision). Virginia creeper and poison ivy, two native vines that are particularly beneficial to wildlife, turn fiery red in fall, usually while the trees around them are still green. Ecologists call this a foliar flag.


A foliar flag: poison ivy growing up a tree trunk turns red in early fall, while the tree that supports it is still green, to signal to birds that its berries are ripe.

But maples and tupelos both flaunt bright red foliage in fall, although their fruits ripen much earlier in the season. Why do the trees waste all the energy it takes to produce red pigment? There are many theories: to protect against insect damage or sunburn at the crucial time of leaf abscission,  or to fool insects into thinking the tree is dying; they’re neatly summarized in today’s NY Times. Read about it there, and be sure to get outside and enjoy the short-lived show. There are lots of lovely red and sugar maples around our area, and even a few tupelos.

I’ll leave you with a brain teaser: the foliage of which native shrub turns a deep purple/pink color in fall?


Native sugar maples are plentiful in our area; they turn beautiful shades or red and orange. Many dogwoods and viburnums turn dark red.



After the storm


The Virginia creeper that covers my garage wall looked like this on Thursday. Today, after the rain, the stems are bare of leaves.

The complex weather system that’s bringing us our first taste of fall is still blowing through–the sun is shining brightly now, but more rain is forecast for tonight. The rain so far isn’t as much as I had hoped; my rain gauge shows about 1 1/4″. According to today’s NY Times, rainfall in New York City is still 20 percent below normal for the year. Keep watering!

On the positive side, if you were planning on doing some fall planting, this is the time. The soil is moist and the temperatures are supposed to remain cool this week. The weather is perfect for weeding–pleasant temperatures and moist soil. Once things dry out and the wind dies down, be sure collect some leaves. And we may have a freeze Wednesday night, so harvest your remaining tomatoes and other tender crops. The next few days will be great days in the garden.


Look carefully at the top of the pole and you’ll see an enormous raptor that spend most of Friday afternoon drying its wings in front of my house.

The garden right now


Chokecherry (Prunus virginiana) is displaying a lovely clear yellow color this year. This mid-sized tree is an excellent wildlife plant, like all cherries, but its tendency to form thickets makes it difficult to use in most gardens. You have to give it room to spread.


Many native perennials provide a second burst of garden interest in the form of vivid leaf color. The bright red is sundrops, Oenothera fruticosa.


From left to right: orange chokeberry (Aronia melanocarpa), yellow spicebush (Lindera benzoin), and dark red flowering dogwood (Cornus florida).


A detailed look at those chokeberry leaves.


Seeds of little bluestem (Schizachrium scoparium) turn a tranclucent silver in the autumn sunlight. After the birds eat them, the stalks will turn pink and remain through the winter.


Most perennials have gone to seed, but New England aster (Aster novae-angliae) will continue to bloom for a few more weeks.


Virginia creeper (Parthenocissus quinquefolia) never fails to delight. Its autumn color is usually a brilliant orange red, but right now, the few remaining leaves are a deep russet.

These photos were all taken yesterday. Enjoy the bright colors on this dark, rainy day. And remember how badly we need the rain!

Autumn unfolds

I started to show you pictures of fall color on September 11; it’s six weeks later and our local trees are just reaching their peak. The sugar maples (orange) and hickories (yellow) are particularly beautiful this year. I’m not fortunate enough to have either–the soil is wrong for them in this part of Glen Rock–but I do have dogwoods, Virginia creeper, and lots of native perennials that show lovely fall color. So here’s what’s happening in my garden now.



Virginia creeper ranges in color from a delicate peach to the deepest Bordeaux. And sundrops (Oenothera fruticosa), a ridiculously easy-to-grow native plant with bright, bright yellow flowers in early summer, puts on a second show in fall, when its foliage becomes speckled with red.


Thoreau sketched the beautiful arrangement of milkweed seeds in their pods. It’s fascinating to watch the clusters of seeds slowly unfold as the wind teases them apart. This fascinating process is happening in my garden right now. Sometimes I watch and forget to collect the seeds.


And finally, about 20 years ago we planted five everbearing raspberry canes from Burpee, because we love raspberries. When my now grown-up sons come home to visit, they still go outside to look for raspberries. Although the canes are crowded by perennials on one side and the mini-forest on the other, they continue to produce fruit every year. The catbirds in particular adore them, and in fall, when they’ve left for the season, we manage to eat a few raspberries ourselves.


A little hint of early summer in the middle of fall (complete with fruit fly). And notice the Rudbeckia seedheads on the left.

It’s not too late to put in some raspberries. You could be enjoying your own crop next year.

10/17/14: In the garden this week


For once, the picture really doesn’t capture it. I wish I could convey the exact shade of pink/orange/red/scarlet of the leaves of Virginia creeper (Parthenocissus quinquefolia). I guess you’ll just have to grow it for yourself. It’s spectacular. The only vine that rivals it as a foliar flag is our old friend poison ivy. To find out why vines, in particular, turn such brilliant colors, look at this post.

We tend to think of autumn as a time of dormancy, but plants are extremely busy with winter preparation. Some things they do are obvious, such as when the huge acorns of northern red oaks or swamp white oaks hit the roof (some parts of Bergen County are having a mast year now; we had one around here last year). Autumn colors mean that plants are stopping photosynthesis, withdrawing green pigments and revealing other underlying colors. Next year’s buds have formed, and many perennials are putting out rosettes of new foliage. Some fruits are very prominent, some are already gone, snatched up eagerly by migrating birds. The plants are working hard to prepare for winter, taking advantage of the autumn sunshine.

Here’s what you can be doing now, in addition to admiring all the hard work your plants are doing:

water newly installed perennials and woody plants and vegetables as needed. The recommended amount is 1 inch per week during dry spells, but we received a good soaking this week (3 inches of rain according to my yogurt-container rain gauge), so hold off for now.

do not prune woody plants. Trees and shrubs are carrying out leaf abscission, the complicated process of shutting down for winter. (That’s what makes those lovely colors.) This process takes a lot of energy, so plants don’t have energy to spare for making scar tissue. The next pruning window will come when plants reach dormancy in late fall.

– harvest fall crops such as lettuce, spinach, and other salad greens. Harvest winter squashes. Remove spent plants. Do a thorough clean-up of the vegetable garden. Do not compost diseased or pest-infested plants. Spread a layer of compost over the vegetable garden to prepare the soil for next year.

established perennials should need no care. Leave seedheads in place–birds will eat the seeds you don’t collect.

save your autumn leaves for compost. Decide where you will keep them. Consider mulching them into your lawn as fertilizer; this is easy to do with a mulching mower.

consider fall planting. It’s getting to be a bit late to plant perennials, but many woody plants can be planted until the ground freezes.

Relax and enjoy the beautiful autumn colors!

Native plants for fall color

My husband takes most of the pictures on this blog (all of the good ones). Within the last hour, he walked around the garden and took pictures of the perennials that are in bloom and the shrubs that are showing fall color. We’ve had quite a cool summer, and it’s been very dry for the past month (and I have not watered), so it seems to me that the garden is a week or two ahead of where it should be right now: late-blooming perennials are further along than they are in most years, and some woody plants are shutting down a bit sooner than usual. But there’s still a lot going on in the garden.


New England asters are always the star of the autumn garden, attracting pollinators well into October. This is a unknown cultivar of Aster novae-angliae that’s been in my garden for about 20 years.


This is Aster oblongifolius ‘October Skies,’ which I purchased only yesterday. The plants are still in their pots, but the bees don’t care.


Notice the bee theme we have going here. Yet another pollinator is enjoying this lovely goldenrod, species unknown, that volunteered in my garden many years ago.


Yet another volunteer plant is white snakeroot (Eupatorium rugosum), a native perennial that started to appear in this area about 10 years ago and is now common. Look closely–there are lots of pollinators on this one.


And still another volunteer in my garden. I believe this is heath aster (Aster ericoides).


We planted Virginia creeper on the side of our garage about 15 years ago. It feeds the birds in fall and rewards us with gorgeous fall color.

Foliar flags


This picture, taken last fall along the PSE&G right of way that cuts through Hamilton Avenue in Glen Rock, shows what ecologists call a foliar flag. This vine–you know that it’s poison ivy, right?–turns brilliant red in early fall just when its berries ripen. And it doesn’t do it for our aesthetic enjoyment. It does it to advertise to the birds that its berries are ripe–that’s the flag. When the vine’s leaves are green it’s hard to see the plant among the tree leaves, so the vine has to do something special so the birds will eat its berries and scatter its seeds.

Here’s another picture of poison ivy doing its autumn thing taken a few days ago in the Thielke Arboretum.


Poison ivy does not hurt the trees it climbs, and it has especially nutritious berries that are devoured by many, many species of birds. Also, despite its scary name, many people are not allergic to it. Of course we need to remove it from places where children play, but we also need to remember that it plays an important ecological role and leave it along in natural areas. It is native and does not become invasive.

Another native vine that turns gorgeous fall colors is Virginia creeper (Pathenocissus quiniquefolia). Like poison ivy, it has nutritious berries that birds seek out and that ripen in early fall, so it too produces a foliar flag. also like poison ivy, it does not harm the trees or structures it climbs. If you have an ugly brick wall you would like to cover, consider this lovely plant.


Both these vines are very common in our area. They’re easy to tell apart: Virginia creeper has leaves made up of 5 leaflets. Poison ivy has three shiny leaves that are reddish in early spring, bright green in summer, and orange or red in fall.


Gorgeous, aren’t they?