Seasons: Fall

Fall

I have been treading on leaves all day until I am autumn-tired.
God knows all the color and form of leaves I have trodden on and mired.
Perhaps I have put forth too much strength and been too fierce from fear.
I have safely trodden underfoot the leaves of another year.

-from 'A Leaf-Treader', by Robert Frost

Take a Self Guided Fall Color Tour around the campus!

The San Francisco Bay Area often experiences an "Indian summer" in September and October. The coastal areas are free of the summer fog, and inland, temperatures at times climb into the 100s. Students return to campus at the end of September, making the preceding weeks a busy time for the Grounds Department.

Continuing through the fall and winter are the department-sponsored Groundskeeper training
classes that begin in summer. The classes are
part of a four-session program covering plant identification and basic horticulture, which includes everything from introductory botany to pest control. The program prepares our groundseepers to become Certified Landscape Technicians (or CLTs). This certification is obtained by passing a rigorous test offered twice a year by the Associated Landscape Contractors of America.

In preparation for the rainy season, the Clean-Up Crew checks and cleans storm drain grates throughout campus. Leaves and fallen fruits can accumulate along road edges as well as roofs, gutters and downspouts. The crew keeps busy in October, with leaf cleanup along roadways in full swing.

Some native plants come out of dormancy as the rainy season begins, usually in November, when sunny days alternate with showery and windy ones. This adaptation of leaf loss in summer and leaf growth in winter is seen in a variety of California plants, such as chaparral flowering currants (Ribes malvaceum) and buckeyes (Aesculus californica). Other native plants that grow along creeks or in areas where the water table is high exhibit the more familiar winter dormancy, such as is found in plants east of the Rockies. These include the white or valley oak (Quercus lobata) and dogwoods (Cornus species).

The warm soil and free irrigation (i.e. rain) in fall make this one of the best times to plant. In fall, we prepare for the spring wildflower display. The areas are disked and reseeded. Many perennials are best divided at this time, such as the Douglas iris (Iris douglasiana) in the Serra Groves, the daylilies (Hemerocallis hybrids) along Galvez Mall, and cool-season ornamental grasses, such as tufted hair grass (Deschampsia cespitosa) and common blue fescue (Festuca glauca).

Lawns throughout campus are renovated in the fall. This involves aerating, fertilizing, and overseeding as necessary. Grass seed sprouts and grows well through the cool months; sod also establishes better when fall-planted.

As summer weeds go to seed, winter annual weeds germinate. Many insects overwinter either as eggs or adults, so there is less feeding and subsequent plant damage. The spray crew power washes the trunks of selected oak trees with water under high pressure, as part of our Integrated Pest Management program. This removes egg and cocoon masses of the Western tussock moth, in areas that have been "hot spots" in past springs.

Cold nights can damage frost-tender plants beginning in November in some years. In the Arizona Garden, some cacti are protected from the deadly combination of wet and cold with Saran wrap "shower caps." Cold-sensitive plants are moved to protected sites.

Campus Blooms and Fall Color

Two unusual plants for the Bay Area are in full bloom on campus in September: the Natal coral tree (Erythrina humeana) and floss silk trees (Chorisia speciosa). Both are from subtropical climates and lend an exotic air to the area around White Plaza and the Inner Quad. The Natal coral tree, located at the southeast corner of the Old Union, is from eastern South Africa and is covered in red "candles" from fall through winter, at a time when it begins losing its leaves. Similarly, the deciduous floss silk tree, located in the Inner Quad and at the Post Office, glows under a cover of large hot pink flowers in late fall. The rest of the year, the unusual spiny green trunk provides additional interest.

Crape myrtles (Lagerstroemia indica) are from China. In addition to plumes of flowers in an array of colors, these trees have beautiful peeling bark and brilliant yellow to red fall color. They are in full flower here from July through September, along Galvez Street, Campus Drive East near Junipero Serra Boulevard, and Via Ortega at Panama St.

The dazzling fall color displays of the Chinese Pistache (Pistacia chinensis) along Bowdoin Street as well as Santa Teresa Street are not to be missed. The dawn redwoods (Metasequoia glyptostroboides) in the Law School Lawn also turn rust in color at this time, but this is not a cause for alarm. They are actually one of the few deciduous conifers and a long-lost cousin of our coast redwood (Sequoia sempervirens).

Other spots to view fall color:

Common Name Botanical Name Location
Sour Gum, Tupelo Nyssa sylvatica Quad - south side of buildings 60 - 70
Chinese Tallow Tree Sapium sebiferum Escondido Road at Manzanita Park
Ginkgo Ginkgo biloba Upper Galvez Mall, Gilbert Biology, Segal Sculpture
Japanese Maple Acer palmatum Green Library - north side, Hoover Building Courtyard
Sawleaf Zelkova Zelkova serrata Via Palou, Escondido Village at the end of McFarland Court
Tulip Tree Liriodendron tulipifera Tresidder lawn
Crape Myrtle Lagerstroemia indica Galvez Street
Washington Thorn Crataegus phaenopyrum Mayfield Mall
Ornamental Pear Pyrus calleryana Schwab Center
Eastern Redbud Cercis canadensis Schwab Center - south side at Manzanita Park
Western Redbud Cercis occidentalis Rains Housing
Modesto Ash Fraxinus velutina 'Modesto' Between Post Office and Bookstore, Bowdoin Street
Boston Ivy (vine) Parthenocissus tricuspidata Graduate School of Business
Persian Parrotia Parrotia perska Gilbert Biology

Month-by-Month in Your Garden

September:

  • Clean roof, gutters, downspouts, storm drains in preparation for winter rains.
  • Harvest flowers and herbs for drying.
  • Harvest last of summer crops and plant fall-winter crops.
  • Plant broccoli, cauliflower, radishes, beets, spinach, peas, Swiss chard.
  • Transplant starts of winter annuals or young plants.
  • Buy spring-flowering bulbs.
  • Trim bearded iris to 6-inch height.
  • Prepare wildflower beds - soak to germinate weed seeds, then hoe or hand-pull.
  • Plant new lawn (seed or sod). Begin pruning trees - fall is a good time to correct poor structure, to remove diseased or damaged wood, and to direct and control growth.

October:

  • THIS IS THE BEST TIME TO PLANT FOR PERMANENCE.
  • Plant trees, shrubs, groundcovers, perennials. The summer-warmed soils stimulate root development, the low angle of the sun is less intense, and winter rains will help with irrigation.
  • If removing fallen leaves, place them in a compost pile. Retain fallen leaves wherever possible to recycle nutrients back to plants.
  • Plant bulbs for spring bloom, then overplant beds with fall-planted annuals.
  • The following add color over the winter:
Common Name Botanical Name
Snapdragon Antirrhinum majus
Flowering cabbage Brassica oleracea
Pot marigold Calendula officinalis
Florists cyclamen Cyclamen persicum
Sweet pea Lathyrus odoratus
Stock Matthiola incana
Nemesia Nemesia strumosa
Iceland poppy Papaver nudicaule
Primrose Primula spp.
Viola Viola cormuta
Pansy Viola x wittrockiana
  • Order bare-root grapes, fruit trees, berries mail order or through your local nursery.
  • Protect cold-sensitive plants against early frosts.

November:

  • IT'S STILL A GOOD TIME TO PLANT FOR PERMANENCE.
  • Continue planting trees, shrubs, perennials, vines.
  • Water plants regularly if rains fail to come.
  • Wait until spring before planting frost-sensitive plants.
  • Continue transplanting winter vegetables.
  • Sow wildflower seeds.
  • Divide bulbs, cool-season ornamental grasses and clumping perennials.
  • Prune top-heavy plants to minimize storm damage.
  • Cut chrysanthemums to 3" from soil.
  • Control snails and slugs (hand-pick).
  • Spray fruit trees with dormant oil after leaves have dropped (fixed copper for brown rot on apricots, lime sulfur for peach leaf curl).