Russian Olive

What’s happening: Cold dry mornings have been killing off many leaves that remained; rose leaves, some junipers and the edges of some prickly pears bronzing; gumweed seeds disappearing.

What’s still green: Juniper and other evergreens, Apache plume, yuccas, Japanese honeysuckle, pyracantha, red hot poker, grape hyacinth, Jupiter’s beard, large-leaved soapwort, sea pink, snapdragon, hollyhock, oriental poppy, blue flax, yellow and pink evening primroses, vinca, gypsum phacelia, tumble mustard, snakeweed, dandelion, anthemis, some coreopsis, perky Sue, Shasta daisy, some black-eyed Susan, strap leaf aster leaves; June, pampas, brome, cheat and base of needle grasses; young chamisa branches.

What’s grey, blue-grey or grey-green: Piñon, four-winged salt bush, buddleia, pinks, snow-in-summer, loco weed, yellow alyssum, stick leaf, western stickseed, winterfat, Silver King artemisia, golden hairy aster leaves.

What’s red/turning red: Privet, rose, cholla, prickly pear, small-leafed soapwort, beards tongues, coral bells leaves.

What’s yellow/turning yellow: Arborvitae; globe and weeping willow branches.

What’s blooming inside: Aptenia, asparagus fern.

Animal sightings: Now that leaves have fallen, I can see several birds' nests in my neighbor’s apricot, the one near the road with a number of vertical branches that grew after it was pruned.

Weather: Cold morning temperatures are earlier than usual; last rain 10/21/10; 9:47 hours of daylight today.

Weekly update: If I took the number of volunteer plants in my yard as an indicator, then the birds in this area prefer the berries of Virginia creeper and Russian olive over all others.

Hawks Aloft found, when it monitored birds in the bosque between Rio Rancho and Los Lunas for the Corps of Engineers between 2003 and 2008, that the Russian olive, so disparaged by environmentalists for filling the void left by the disappearing cottonwoods, is actually filling a much larger hole for migrating birds whose habitats are vanishing with suburban development. The highest densities and greatest diversity of species in winter were found in pure stands of Elaeagnus angustifolia.

The native of the collision belt between the Eurasian continent and the more southerly plates begins leafing the middle of April. The four-lobed tubular flowers appear a month later on branches they have lengthened from buds formed the previous year. However, you only know because you can smell them. The small pale yellow clusters are hidden by umbrellas of narrow, grey leaves on reddish twigs covered with grey scales.

Last year I saw incised fruits on my tree the first of July. They were gone before the end of summer. The tree in the wide arroyo produced small, round grey-green olives the middle of July that were disappearing by the end of September.

Unlike many deciduous trees whose leaves turn color, then drop, Russian olive leaves seem to just dry in late September and fold into narrow pendants that won’t hold ice or snow if the weather turns bad prematurely and make the ripening berries more visible. If they’re not eaten, the polished tan berries can last until late winter, when they begin to shrivel.

Hawks Aloft found many birds ignored them in the fall, if there was a large sunflower crop. However, neo-tropical animals like Wilson’s Warbler and the Western Tanager ate the berries, as did migrating robins, hermit thrushes, and white crowned and song sparrows.

The fruit continues to age during the cold, when it’s more important for birds wintering in the bosque. For instance, Stellar’s Jay was there in 2008 when the cone crop was less plentiful at higher elevations. Eastern blue birds have become permanent residents. Others that eat the fruit in the shortened days include western and mountain blue birds, both types of sparrows, American robins, red-winged blackbirds, northern flickers, hermit thrushes, yellow-rumped warblers, spotted towhees, and dark-eyed juncos.

Russian olives continue to be important in spring, when little new has appeared in the landscape. Of the 18 vegetation communities observed by Hawks Aloft from 63 locations, the nitrogen fixing members of the oleaster family attracted the second highest density of terrestrial birds, and were particularly important to cedar waxwings. In other parts of the country, those birds eat pyracantha berries in fall.

Where I live is close enough to the river to hear migrating geese in the morning and see occasional flocks overhead, but too far away to attract visitors. Occasionally a robin will appear in late May, usually near the orchards and open fields near the village.

The orchards provide both the remains of previous crops and large swaths of non-native grasses, like smooth brome, with all the seeds, insects and worms they bring. They also have no dogs, infrequent human visitors, and cars that are a goodly distance away.

This spring was unusual. Robins seemed to have started out earlier than usual, then were forced to lay over in this less than optimal area. I saw one along the side of the main road in February, when I was also hearing water fowl. The end of the month, I saw larger numbers around the orchards.

The middle of March, some had moved two miles south to my uphill neighbor’s yard, especially the area where the previous owner had kept horses. The end of the month, two small birds were in my catalpa. The next day one was in the peach next to my house. In mid April, there was one in the cottonwood between the catalpa and the old paddock. I last saw a robin in a front yard orchard on the main road the end of May.

Meantime, I saw some unusual slate-blue colored birds with brighter, darker heads on May 2 in the still barren Russian olives that line a lot next to the other, narrower arroyo that has the remains of some kind of lawn. I don’t know if those trees still had berries - it’s much harder to see such things in someone else’s yard - but this fall they have large fruits, while my tree and the one in the wide arroyo produced nothing this summer.

The skin color has faded to bleached wood. Most still have pockmarked surfaces, but the sides of some are becoming smooth and glisten in the sun. When one’s plucked, the short stem snaps, but the fruit resists pressure. However, when it’s broken, the outer skin is as pliable as an orange peel. The layer between the rind and the large seed has begun to dessicate: the mesocarp crumbles in the fruits that have begun to turn golden, is a bit more adhesive in the less mature ones.

At this time, the fructose and glucose are concentrated in the rind, but the drying pulp still has some flavor. When Steve Brill bit into a ripe fruit, he said "it tasted great - like a sweet raisin - for the first five seconds. Then it seemed like I had a mouthful of talcum powder."

Local birds, like the smallish brown ones that moved into my eastern neighbor’s metal building, have no problems eating the mealy drupes. A tree is now growing at the corner of his barn, and I suspect that that tree is the source of all the seedlings I removed from areas near the utility line this spring.

Whether or not natural selection is purely random or has purposefully favored the trees that support symbiotic birds is a philosophical, perhaps even a theological question. What’s obvious is that the large, striped seeds obviously aren’t damaged by their middle passage.

Notes: Thanks to an anonymous friend who was willing to taste the separate parts of a berry.

Brill, Steve. Identifying and Harvesting Edible and Medicinal Plants, 1994, with illustrations by Evelyn Dean.

Hawks Aloft, Albuquerque. Bird and Vegetation Community Relationships in the Middle Rio Grande Bosque: 2008 Interim Report, May 2009.

Photograph: Russian olive berries on a tree near the narrow arroyo, 5 December, 2010; the joint between this year’s growth and last is clear with the change in branch color; buds for next year’s growth and the dried tear drop leaves are also visible.