Column
Date:
October 7, 2014
Contact:
JoAnne Skelly, Carson City / Storey County Extension Educator,
University of Nevada Cooperative Extension, 775-887-2252, [email protected]
Spring Bulbs Need Fall Planting
I’m looking forward to planting daffodils this
weekend. They were so lovely last spring; I want more.
Spring flowering bulbs need fall planting and October
is the best planting time. Once planted, bulbs require
little maintenance for long-term visual pleasure. Among
the most popular types of bulbs are tulips, narcissus,
daffodils, hyacinths and crocuses.
For the best display next spring, start with large
firm bulbs. Smaller, less expensive bulbs will have less
food reserves and will produce fewer flowers on
weaker stems. Avoid bulbs with blemishes,
discoloration, moldy skin or rotten bits.
Select a site for planting where the bulbs will
receive a minimum of five to six hours of sun each day,
although daffodils, fritillaries or wood hyacinths will
tolerate some shade. Ideally, the soil in your selected
location should be porous and well drained.
Dig a hole for each bulb, or dig one large area,
big enough to hold all the bulbs in one drift. Bulbs
planted in irregular patterns and masses of just one
color look more natural than those planted in soldierly
rows. Bulbs can be planted in with ground covers and
other flowers. The general rule for planting depth is to
plant bulbs two to three times as deep as the bulb
diameter. Plant them as far apart as the depth at which
they are planted – four to six inches for large bulbs,
one to two inches for small ones. In poorer draining
soils, plant bulbs a little higher to prevent them from
rotting.
Loosen the soil in the bottom of the hole. Mix in
compost and bone meal, superphosphate or a
commercial bulb food into the bottom of the hole.
Balanced fertilizers high in phosphorus (the second
number in the analysis) such as a 5-10-5 or 5-10-10
can be used instead. Plant the bulbs with the flat or
concave side down and the pointed side up. Press the
bulbs gently into contact with the bottom of the hole and
cover with the amended soil. Tamp the soil down firmly
around the bulbs. This will eliminate air pockets that
prevent good root development. Water thoroughly and
apply a 3-inch layer of mulch for winter protection. Water
once every week or two through the fall and at least once
a month through the winter.
After a long winter of often-gray days and little
color in the yard, that first burst of spring color will be a
welcome sight.
Column
Date:
October 14, 2014
Contact:
JoAnne Skelly, Carson City / Storey County Extension Educator,
University of Nevada Cooperative Extension, 775-887-2252, [email protected]
Why Do Leaves Change Color?
Autumn has come gently this year with hot weather continuing into October. The leaves are
finally turning color. At University of
Nevada Cooperative Extension,
Master Gardeners are often asked
why leaves change color. Is the cold
responsible? This seems logical, but
it is not the complete answer. Many
leaves start to change long before
the cold weather hits. The most
important factors affecting the colors
are the change in daylight and day
length.
Four leaf pigments are
responsible for the colors in leaves.
These are chlorophylls, carotenoids,
anthocyanins and tannins. At this
time of year, leaves slow their foodmaking process (photosynthesis)
preparing for winter shutdown.
Chlorophyll begins breaking down
and disappears from leaves.
Chlorophyll gives plants their green
color through spring and summer.
When the green color fades, other
pigments show through, such as the
carotenoids, which give leaves their
yellow and orange colors.
Previously, these colors were
hidden by the green chlorophyll.
Although temperature does
influence the process, day length
and the reduction of chlorophyll
production are the controlling
factors.
Other plant chemical changes also occur during autumn producing the red and purple colors
we see in plants such as sumac, Virginia creeper, burning bush and others. The fall weather
conditions that favor brilliant red color are warm sunny days with crisp nights without freezes. The
cooler nights trap sugars that were produced in the leaves during the sunny day. This allows the
anthocyanin pigments to produce red color tones. Anthocyanins are usually only produced in the fall.
Tannins produce the brown tones in fall leaves. They accumulate in dead tissue. Brown leaves are
simply waste materials leftover in leaves.
Fall color is also affected by what happened to the plant during the growing season,
particularly in regards to moisture. Rainy cloudy weather can reduce fall color because sugar
production is reduced when there is less light intensity. Summer drought can play a role by delaying
the onset of fall color by a few weeks. Since soil moisture varies from year to year, no two autumns
are ever alike. Color intensity varies with location, from sunny exposures to shady ones. Color can
even vary on individual trees or by tree types. Early frosts weaken the strong colors because leaves
are injured by the cold.
Call 887-2252 or email [email protected] for a free copy of “Preventing Winter Injury to
Landscape Plants.”
Column
Date:
October 21, 2014
Contact:
JoAnne Skelly, Carson City / Storey County Extension Educator,
University of Nevada Cooperative Extension, 775-887-2252, [email protected]
A Bee-friendlier Society
“In 1945 there were 4.5 million bee hives in the US. Today, there are just about 2 million. We
average a 30 percent loss of beehives in winter each year. Twenty years ago that was 15 percent.”.
So reports Dr.Marla Spivak, entomologist, University of Minnesota Bee Lab in a 2013 Ted Talks
presentation. She says there are 20,000 species of bees in world. Most live in the ground or in hollow
stems rather than in social colonies as honeybees do. Within a colony, bees have natural defenses
that have kept them thriving for over 50 million years. However, seven years ago, bees started dying
from multiple, interacting causes: disease-causing parasites, monocultures of plants, pesticide
contamination, flowerless landscapes and a dysfunctional food system.
In the US, bee numbers have been declining since World War II when we changed our farming
practices. We stopped planting clover and alfalfa cover crops, which were an excellent food source
for bees and started using synthetic fertilizers instead. We began applying more herbicides, killing
weeds whose flowers were a food source for bees. Now farms are agricultural food deserts for bees,
because they are usually dominated by single species (monoculture) of plants. For example, even
though almond flowers are a good pollen source for bees, over 1.5 million hives must be transported
across the country to pollinate tens of thousands of acres of almonds. Nothing else is growing, just
almonds. The bees are trucked in on semis and trucked out after pollination, since at that point, there
is no more food for them.
After World War II, farmers also increased their use of fungicides and insecticides, in addition
to herbicides. Researchers at Penn State University have been studying pesticide residues in the
pollen bees are carrying home. They found that every batch of pollen in their study had about six
pesticides in it, including not only the toxic active ingredients in the herbicides, fungicides,
insecticides, but also the inert ingredients that can be more toxic than actual chemical.
What can we as gardeners do? We can plant bee-friendly flowers, particularly native plants
that bloom in each season. We can avoid pesticide contamination, at least in our own yards. We can
ask that pollen sources be planted in parks, open spaces, along roadsides, etc. We can give bees
access to good nutrition, which will allow them to take care of their own health. We can be a bee
friendlier society.
For more information go to:
http://www.ted.com/talks/marla_spivak_why_bees_are_disappearing?language=en
Column
Date:
October 28, 2014
Contact:
JoAnne Skelly, Carson City / Storey County Extension Educator,
University of Nevada Cooperative Extension, 775-887-2252, [email protected]
Herbicides and Weed Resistance
The Environmental Protection Agency (EPA) sent out a press release announcing a decision
to register a new herbicide that contains two active ingredients, 2,4-D and glyphosate. These two
ingredients are the most widely used herbicides in the world for controlling weeds. Local gardeners
use 2,4-D to kill dandelions in lawns and glyphosate to kill just about anything green. This new
herbicide combo is designed primarily to kill weeds in corn and soybeans; crops that have been
genetically engineered to tolerate both chemical compounds.
EPA scientists used very conservative assessments to evaluate not only the human health
risks, but also the ecological risks. The agency evaluated the risks to all age groups, from infants to
the elderly, and took into account exposures through food, water, pesticide drift and as a result of use
around homes. The decision meets the rigorous Food Quality Protection Act standard of "reasonable
certainty of no harm" to human health. The assessments confirm that these uses meet the safety
standards for pesticide registration and, as approved, will be protective of the public, agricultural
workers and non-target species, including endangered species.
While genetically engineering plants to tolerate chemicals that would normally kill them allows
farmers to kill weeds more easily, weeds quickly build up resistance to new herbicides. In a few
years, the herbicides no longer work to control weeds in the crop and new chemicals must be created
or combined and additional genetic engineering must occur. Resistant weeds become quite costly to
a farmer, who no longer can use that method of control. Those costs are usually passed on to the
consumer. To ensure that weeds will not become resistant to the 2,4-D/glyphosate combo, EPA is
imposing a new, robust set of requirements on the company registering the product. These
requirements include extensive surveying and reporting to EPA, grower education and remediation
plans. The registration will expire in six years, allowing EPA to revisit the issue of resistance. In the
future, the agency intends to apply this approach to weed resistance management for all existing and
new herbicides used on herbicide-tolerant crops.
Although this combination herbicide may not be registered for use in Nevada in the near future,
home gardeners, farmers and others use many other herbicides. Overuse of any herbicides or
repeated use of the same herbicide can create resistance in the common weeds we deal with in
Nevada. Use herbicides as a last resort. If you do apply herbicides, use products with different active
ingredients each year to avoid creating resistant weeds.