Sept. 15-21, 2014

As we lay awake long before daybreak, listening to the rippling of the river and the rustling of the leaves ... we already suspected that there was a change in the weather, from a freshness as of autumn in these sounds. That night was the turning-point of the season. We had gone to bed in summer, and we awoke in autumn; for summer passes into autumn in some unimaginable point of time, like the turning of a leaf.

-Henry David Thoreau

Lunar phase and lore

The Puffball Mushroom Moon, entering its last quarter on Sept. 15, weakens throughout the period, reaching its least influential position of apogee (when it is farthest from Earth) on Sept. 20. Rising at night and setting in the afternoon, this moon travels overhead in the morning, encouraging fish to bite and animals to be more active, especially as the cool fronts of Sept. 15 and 20 push down the barometer before their arrival.

The dark moon in Gemini between Sept. 14-16 and in Leo on Sept. 18-21 may be advantageous to harvesters. Plant bulbs under Cancer on Sept. 16-17.

Weather trends

The chances for highs only in the 60s move from 10 to 30 percent this week, and cold afternoons in the 50s become possible for the first time since June 4. The likelihood for warm 90s or 80s falls sharply throughout the period, with Sept. 18 bringing only a 20 percent chance for highs above the 70s, the first time that has happened since May 6.

Each day this week brings at least a 30 percent chance for showers, with Sept. 18 having the highest chance: Almost 50 percent.

Now the chance for a light frost to occur in a seven-day period is up to 40 percent. Next week it will be 50 percent. In two more weeks, it will be 80 percent, and in three weeks, almost 100 percent.

The natural calendar

Sept. 15: The high amount of sunlight and continuing mild temperatures generally keep people in good spirits this week of the year. Although the day has lost three hours since the middle of summer, the remaining 12 hours are usually enough to maintain emotional balance.

Sept. 16: In the final two weeks of September, a rapid deterioration occurs in all the wildflowers except the goldenrod and asters.

After these last flowers go to seed in early October, there is no new generation of blooming plants to replace them.

Sept. 17: As the sun moves to within a few degrees of equinox, late summer’s grip grows measurably weaker. When the mid-September weather system moves along the 40th Parallel, brisk afternoons in the 50s or 60s are four times as likely to occur as during the first week of the month. The weakening moon, however, should soften the effect of this system.

Sept. 18: More hickory nuts and more acorns come down. Wood nettle seeds are black and brittle. Black walnuts are all over the ground. The huge pink mallows of the wetlands have died back, heads dark, leaves disintegrating.

Sept. 19: In the woods, ground ivy, mint and catchweed revive as the canopy thins. Waterleaf has fresh shoots. Snow-on-the-mountain has recovered from its mid-summer slump and can be as thick and as beautiful as in early spring.

Sept. 20: This week the odds for an afternoon in the 50s or 60s doubles over those odds last week. The pollen season, however, declines quickly after the passage of the equinox weather system, and lunar apogee today decreases the likelihood of seasonal affective disorders.

Sept. 21: The Piscid meteors fall through Pisces, in the southern sky, on the night of Sept. 21, and the dark moon will not interfere at all with your watching for these shooting stars.

In field and garden

Sept. 15: Half the potatoes are usually in by today. About a third of the soybeans are ordinarily shedding leaves. Mum season peaks in local nurseries.

Sept. 16: The dark waning moon of September’s third week favors vaccinations, surgery and general livestock care. Changes in the season bring weather extremes as well as stress, so you will be taking care of routine health care at the most important time of the year.

Sept. 17: Prepare cold frames to lengthen the seasons of select vegetables and flowers through November. Begin to bring in house plants and herbs that you have set outside for summer sun. Clean out storage areas for the gladiolus and dahlia bulbs you will dig before a hard freeze.

Sept. 18: Plan to renew some of your pastureland by putting in an “antiseptic crop” of mustard, radishes and turnips.

Sept. 19: Most weeds and wildflowers have gone to seed in the field and garden. The last summer apples have been picked.

Sept. 20: Half of the corn is now ordinarily mature, and farmers have usually harvested up to 10 percent of the crop.

Sept. 21: Adult pine weevils may be active in the evergreens.

Leafturn notebook

The leaves began to turn in July, mostly buckeyes in the woods, but that was a false start. Then in August, the foliage of black walnuts started falling, the walnuts coming down beside them.

The real days of seasonal reckoning occur now in the third week of September. Between Sept. 13-20, the first major acceleration in the coloring of trees take place.

Yellows and tans, born in summer’s drier days, spread like the cold nights creeping south.

The summer green of a few sycamores, locusts, elms, box elders, maples, poplars, cottonwoods and redbuds is breaking down. At the same time, goldenrod passes full bloom, the roadside grasses are dry, the corn is mostly brown and the soybeans and milkweed are almost all turned. The land is forgetting July.

Patches of deep scarlet in the sumac and Virginia creeper highlight the changes in the tree line. The rare August Judas maple multiplies. There are streaks of bright amber on the lindens and ginkgoes, tulip trees, locusts, mulberries, chinquapin oaks and osage orange.

In the last days of September, the major autumn leafturn always begins, and the smell of fallen leaves starts to fill the afternoons. In the earliest years dogwoods flush pale pink, and the deepening of hickory and maples intensifies. A few sweet gum, locust and poplars show their finest gold.

By the first day of October, the lower trees and wildflowers in the woods have thinned out, nettles and touch-me-nots as bare as scrub buckeyes and box elders. Some cottonwoods are just about gone. Catalpas are shedding, wild cherry and slippery elm fading, wild grape leaves yellowing and browning along the fence rows.

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