Tuesday, December 31, 2013

Six Ways to Reduce Your Pesticide Use

It's the New Year ~ that time of year when many people resolve to do something better in the coming year, than perhaps they did in the past year.  Most resolutions have to do with getting healthier in some way, shape or form ~ whether it our physical health or our financial health.

In case your resolution has to do with your garden's health, I thought I would offer up XX ways that you can work towards reducing your pesticide use.  Some of these approaches require nothing more than a shift in perspective.  Others will take more time and effort.  But all are capable of having the effect of reducing pesticide use ~ which is generally good for the health of our environment, pets and families. 

1. Stop acting like organic pesticides aren't pesticides.  Many people believe that anything labeled with the term 'organic' equals 'no pesticides'.  They mistakenly believe that organic produce hasn't been sprayed with pesticides.  They mistakenly believe that they can use a pesticide labelled as 'organic' with total impunity.  And unfortunately, some folks tend to use more pesticide, simply because the pesticide is labelled as 'organic'.  As a general rule, pesticides ~ including organic pesticides ~ are formulated to kill or deter something.  Stop spraying it everywhere, thinking it's safe.  All pesticides should be used judiciously and thoughtfully ~ taking care to limit use only to when and where needed.
Organic pesticides are still pesticides ~ formulated to kill something.  Use judiciously.

2.  Make peace with spiders.  I adore spiders.  I think they're absolutely adorable!  If you have a chance to look at them under a microscope, you'll see that they're cute and fuzzy ~ not unlike a teddy bear.  And, they're great allies in natural pest control.  But I get that some people are seriously arachnophobic.  If you simply can't tolerate spiders, please don't reach for a pesticide.  The thought simply breaks my heart.  Instead, try to get the spiders to relocate.  If they're on your porch, try installing an ornamental porch bracket that will take away anchor points from web-building spiders.  Or, consider installing a yellow-hued porch light.  Yellow lights attract fewer night-flying insects, which will attract fewer hungry spiders.
Lynx spider in an azalea blossom.
Porch brackets can take away web-building sites for spiders.  Source of image:
3.  Build diversity into your garden.  Diverse gardens, with an array of plant families, shapes, colors, sizes, and bloom times also tend to have a diversity of insect herbivores (sometimes called pests).  But, the trick is that even though diverse gardens tend to have a greater diversity of pests, these pests tend to be at lower abundance!  Why?  It may be that a diversity of natural enemies keep them in check.  It may be that a diversity of plants keeps them from exploding in abundance on a single plant type.  Or, it's more than likely a combination of these factors.

Marion Garden in Salem, OR.
Marion Garden in Salem, OR.

4.  Rethink your approach to early-season lawn weeds.  Are dandelions really all that bad?  Not if you love bees.  Our research has found that gardeners who tolerate early-season lawn weeds are likely to have a greater diversity of bees than those who keep totally pristine lawns.  Why?  In early spring, very few flowers are in bloom that offer spring pollinators access to nectar and pollen.  Dandelions are one such flower that helps early season pollinators get a jump on their season.  If you want to keep your lawn dandelions in check, try to dig this perennial weed out, so that you get the entire taproot.  Target young dandelions before they set seed and before they have a chance to grow a large taproot that will nourish them for many years.  Make sure your lawn is healthy and full, to crowd out dandelions.  Or, plant a dense flower bed, with no bare spots where dandelions can flourish.  Or, adjust your tolerance, and recognize that a dandelion isn't the worst thing that could grace your garden.  Invasive plants, such as cornflower (Centaurea cyanus), English Ivy (Hedera helix) or butterfly bush (Buddleia davidii) are much more damaging to the environment and to local economies than are a few dandelions.  It would be much better to target your weed-hating energy towards these plants, than towards dandelions.

5.  Take regular walks in your garden.  This will help you notice when things 'don't look quite right'.  Regular walks in your garden are not only good for the soul, but their good for an IPM approach to managing pests in your garden.  When you notice that something doesn't look quite right, stop and take a closer look.  Often, you'll catch a pest problem in its early stages ~ when it will be easier for you to manage the problem.  Problems caught early usually require fewer (or no) pesticide, compared to those that are allowed to grow out of control.  A corollary to this suggestion is to keep a garden journal.  This will help you track (and remember) the seasonality of pest problems in your garden, so that you'll be better poised to respond quickly.

6.  Talk to the professionals who maintain your lawn and garden.  Ask them if they use an IPM approach to pest management.  Ask them if their staff are up to date on certifications and continuing education requirements.  Ask them what the major pest issues are in your lawn and garden.  Discuss non-chemical options for managing these pests.  If they don't know about IPM, and aren't aware of non-chemical options for dealing with common garden pests, you might want to look for a better-educated lawn care company.

Tuesday, December 24, 2013

During this Season of Giving: Six Garden-Focused Organizations to Consider

In my job, I've been lucky enough to meet so many folks who are passionate . . . and I mean PASSIONATE in their belief that they can help build a better world through gardening.  Some work to feed their neighbors, some work to teach the young, and others work to make gardening accessible to those who don't know how to garden, or those who need help starting a garden.

If you're thinking about making a year-end donation to a garden-focused organization, here are six that could use your help.

I've worked with all of them, in some capacity or another.  Some, I know through grant programs that I've judged.  Others, I know because Master Gardener volunteers support their efforts.  I've sat on the board of one, and know most others from our mutual work on the Oregon Farm to School and School Garden Network.  One, I've made my life's work.  Most of them are too small to appear on, but if a rating does exist, I've posted it next to the organization.

Growing Gardens:  This amazing organization works with volunteers to install raised-bed vegetable gardens in the yards of low-income households.  Those in apartments or with limited space receive container gardens.  Recipients are then supported for 3-years, via a comprehensive educational program (that teaches them how to maintain and use their garden), seeds and starts, and access to garden mentors.  This past fall, they just installed their 1000th garden!

Lettuce Grow:  The Lettuce Grow ('Let Us Grow') Garden Foundation works to install organic vegetable gardens in correctional facilities across Oregon.  In doing so, they help to keep the correctional facility food budget low, while providing healthy and fresh produce to inmates.  Lettuce Grow also facilitates educational opportunities to inmates who work in the garden, by working with the Oregon Food Bank to deliver the Seed to Supper curriculum and by working with OSU Extension to deliver the Master Gardener curriculum in correctional facilities.  Upon successful completion of the Master Gardener curriculum, students earn a Certificate of Home Horticulture ~ a valuable job credential that is of value upon their release.  However, perhaps the most important benefits of the garden programs are their therapeutic effect.  Working the land is healing ~ especially in the high stress environment of a correctional facility.  And, education has the power to create positive social change ~ perhaps more than any other program that I know.  To me, Lettuce Grow offers hope in a place that may often seem hopeless.

Oregon Food Bank:  The Oregon Food Bank partners with OSU Extension to deliver a 5-week, comprehensive gardening course called Seed to Supper.  This curriculum is taught to low income individuals and families ~ teaching them how to grow their own food and to use the harvest in freshly-prepared and healthy meals.  Oregon Food Bank has 3 out of 4 stars on Charity Navigator, with a 70 out of 70 for transparency and accountability, and with 94% of their budget being spent directly on programs.

Food Roots:  I first learned of Food Roots, when they applied for a grant that OSU was offering for school and community gardens.  I was impressed with their application, and even more impressed when I visited their community and school gardens throughout Tillamook County.  They work to support a vibrant food system across Tillamook County ~ via their support of community and school gardens, educational outreach, and micro-enterprise endeavors.  Right now, they're holding a drive to raise funds to build three high-tunnel hoop houses that will be used to hold training classes on how to grow a diversity of fruits and vegetables in the cool climate of the North-Central Coast.  Honestly, I'm amazed at what Shelly Bowe has done in a few short years.  She is a force of good!

School Garden Project of Lane County:  This organization teaches kids about gardening, through in-school lessons and after school gardening clubs.  They assist schools in putting in fruit orchards, or starting a cafeteria composting program.  They also also created a garden-based curriculum for use in elementary schools.

OSU Extension Master Gardener Program:  I'd be remiss if I didn't mention the organization where I work.  We work to train volunteers, who then go on to share what they learned about sustainable gardening with others.  We currently have over 4,000+ volunteers who field close to 200,000 gardening questions each year.  Surveys show that our volunteers and our programs make a difference and promote more sustainable gardening practices.  For example, after participating in our programs or using our services, our clients report that they will decrease or eliminate their pesticide use (68% of those surveyed), work to attract beneficial insects to their gardens (64%), or that they are more tolerant of insect pests (58%) or early flowering lawn weeds (60%).  Those with pest problems report that they intend to switch to more pest resistant cultivars (75%), further decreasing the need for pesticides.  Your dollars can be allocated to support the statewide Master Gardener Program, or to any of the county Extension offices in Oregon with active Master Gardener Programs.  Those few counties with online donation pages are listed, below ~ but you can also go into your local Extension office to make a donation to your local Extension Endowment Fund or Master Gardener Association Chapter.

Wednesday, December 11, 2013

Will this cold snap help keep insect pests down, next season?

It's a beautiful, spring-like day today in Corvallis ~ a welcome relief from our recent spate of freezing weather!  Being half-Filipino and half-Italian, I have a propensity for sunlight etched into my genetic code.  But, I took solace in this recent round of cold weather, by imagining freeze-induced die-offs of key insect pests, in epic proportions.  

How might this current cold snap be wreaking mass entomo-cide on some of my most challenging garden pests? It likely varies across insects.

Azalea Lace Bug (ALB):  I couldn't find any data on the cold tolerance of ALB, other than secondary citations that the bug is hardy to cold weather.  The original publication is Neil, JW. 1985.  Pest-free azaleas can be a reality. J. Azalea Soc. Am. 7: 25-29, but I can't get my hands on that publication.  From the title and the journal, it seems that it would be an anecdotal report that ALB can survive extended periods of cold weather.  This isn't a surprise, since the insect overwinters in the egg stage, the egg is layed INSIDE leaf tissue (offering the eggs protection from cold, predators and parasitoids), and that the egg is covered by an adhesive goo that further provides protection from cold and natural enemies.  It's unfortunate, but this cold snap is unlikely to put a huge dent in ALB populations that we might see next season.
Azalea lace bug adults are about 1/4 of an inch from head to tip.  Start scouting your rhododendrons and azaleas for the first generation of young nymphs, as early as mid-April.  The first clutch of eggs generally hatches in early May, but could be earlier or later, depending upon local weather and other environmental conditions.  Photo Credit:  Robin Rosetta.  OSU Department of Horticulture and North Willamette Research and Extension Center.
If you want to see whether or not your rhododendrons or azaleas have overwintering eggs in them, you can scout your plants anytime between now and the April.  Look for signs of egg-laying damage, on the underside of the leaf, along the mid-rib.  The eggs are super-tiny, but are covered with a tiny brown speck (the adhesive I mentioned, earlier).  Robin Rosetta's fact sheet on ALB has a magnified photo of the eggs.  If you see signs of eggs in your rhodies or your azaleas, mentally or physically make note of which shrubs carry ALB.  Make sure to monitor those shrubs for the first generation egg hatch, anytime from mid-April to mid-May.  One of the best things you can do for season long control is to knock back that first generation of nymphs, so that they don't become adults who will lay more eggs in your rhodies.

Chemical controls are available, but some people have tried to use strong jets of water to knock the nymphs off of the plants.  Whether you use an insecticide or jets of water,  it's important that your shrub canopy is 'open' enough so that your control measure actually reaches the nymphs.  The nymphs feed on the underside of leaves, and in dense rhodie canopies, you will have a harder time reaching the nymphs with an insecticide or a jet of water, compared to a more open canopy.

If that first generation gets past you, ALB will be much more difficult to control.  The bugs are long-lived (by insect standards), and as time passes, you'll start to see an overlap of generations (egg stage, nymphs, adults all occurring together on the same plant).  Control measures, such as chemical controls or streams of water, will help control the nymphs ~ but will be less effective against other life stages, particularly the egg stage.  Keep in mind that chemical controls will also negatively impact natural enemies, such as lacewings, predaceous bugs, spiders and parasitoids ~ all of which have been shown to help naturally suppress ALB populations.

For long term control of ALB, make sure your rhodies are part of a diverse landscape.  Tree canopy cover and other shrubs will help promote spiders ~ one of the main natural enemies of ALB.  Annual wildflowers will provide nectar for green lacewings, which have been shown to help control ALB at a rate of 10 lacewing larvae per shrub.

Brown Marmorated Stink Bug (BMSB):  BMSB are often reported as 'nuisance pests' because they can aggregate in large numbers in your house.  In fact, National Wildlife Federation Senior Scientist Doug Inkley tracked the movement of BMSB into his house, and up to the attic in 2011.  Over the course of 72 days, Dr. Inkley counted 20,116 BMSB in his house!!  You can see from the graph, below, that there was a progressive movement up and into the attic.  Because BMSB overwinters in protected structures ~ like your house ~ this cold snap is unlikely to result in massive die-offs of this insect.

Dr. Doug Inkley tracked the movement of BMSB into his house and up into his attic over the course of 72 days.  Image source:
In addition to being 'nuisance pests' in your house, BMSB can also be a real problem for gardeners.  BMSB use their piercing-sucking mouthparts to probe fruits and seeds.  They can damage pea pods, berries and stone fruits in the garden.  Unfortunately, for home gardeners, there aren't a lot of control options.  Biological controls aren't generally successful, because BMSB have a noxious scent that make them unappetizing to many predators.  Chemical controls are available for this pest, but at best ~ these options provide 'temporary relief' rather than long term suppression.  From our friends back east, we've learned that you just kind of learn to live with BMSB.  It becomes a 'new normal' in the garden.
Brown Marmorated Stink Bug Adults survive the winter by hiding out in attics, barns and other protected structures.  Photo Source:  Brown Marmorated Stink Bug website, OSU Department of Horticulture
Spotted Wing Drosophila (SWD):  We're still not sure how SWD overwinters.  On a sunny, winter's day, you can catch SWD in monitoring traps.  This suggests that the fly overwinters as an adult ~ but it is also quite possible that other stages are present in the winter.  In any case, the fact that we can find SWD in the adult stage, in the winter, bodes well for a massive freeze-induced die off of this berry-feeding fly.
In fact, there was a recent paper published by Danny Dalton (OSU) and colleagues, on the cold-tolerance of SWD, and how adults and pupa react to a 7-day 'freeze' event (Dalton et al., 2011).  And, their data suggests that these generally low winter temperatures, and the recent Willamette Valley, OR 'freeze' event bode well for SWD control.

If SWD are kept in conditions below 50 degrees F for about 30 days, they are super-susceptible to a cold snap.  However, if SWD are kept in conditions above 50 degrees, there are at least some adults that may survive a harsh cold snap, such as the one we've just had.

To see if we've been above or below the 50 degree threshold, I plotted the weather history for Covallis, Oregon over the last month or so ~ and marked on the plot where the threshold is for the 50+ degree F 'safe zone' and the below XX degree F 'freeze zone'.   And it looks like we have plenty of days where the mean temperature was below the 50+ degree 'safe zone', preceding our 7 day 'freeze zone' temperatures.  All of this suggests that this recent weather will help gardeners and growers with Spotted Wing Drosophila populations next season ~ a welcome relief for berry growers and berry lovers across Oregon.

Of course, it's important to point out that the Dalton et al., (2011) experiment was conducted in laboratory growth chambers, with very little organic material that the flies could use as shelter from the cold.  In 'the real world', the flies probably have many more opportunities hunker down from the cold ~ and thus probably have a greater buffer from the cold than my graph might suggest.