A Bustle In Your Hedgerow: California Natives for your Vegetable Garden

Coyote brush (Baccharis pilularis) photo by Art Shapiro

I’ve always been suspicious of some of the popular companion planting advice of the sort dispensed in old books like Carrots Love Tomatoes. From what I understand research just hasn’t proven a lot of the relationships these sorts of books tout. What makes intuitive sense to me, however, is that biodiversity in in a garden can create habitat for beneficial insects and birds that can help keep our edibles free of pests. For thousands of years in Northern Europe that biodiversity was maintained through the use of hedgerows.

Now, thanks to a study conducted by UC Santa Cruz researchers Tara Pisani Gareau and Carol Shennan, we’ve got some solid advice on what sorts of plants can create habitat for beneficials. The study, “Can Hedgerows Attract Beneficial Insects and Improve Pest Control? A Study of Hedgerows on Central Coast Farms” looks at a set of specific plants used in hedgerows in California: common yarrow (Achillea millefolium), coyote brush (Baccharis pilularis), California lilac (Ceanothus griseus and C. ‘Ray Hartman’), perennial buckwheat (Eriogonum giganteum), toyon (Heteromeles arbutifolia), and coffeeberry (Rhamnus californica).

In their conclusion Gareau and Shennan note,

Planting a diversity of plants that have different floral architectures should increase the likelihood of conserving a diverse community of insect natural enemies. Coyote brush and yarrow would be especially important foundational plants in hedgerows. In addition . . . combining hedgerows with in-field floral plantings (in strips or randomly throughout) may increase the dispersal of small-bodied insect natural enemies through the fields.

Scott Kleinrock, who is in charge of the new Ranch project at the Huntington, tipped me off to this research and is making use of a lot of California natives to create the urban residential equivalent of a hedgerow. In short, a hedgerow in our yards and urban spaces means making sure to include lots of natives and flowering plants that can provide habitat for the types of critters we want. Hopefully this important research will be duplicated in other regions and climates with different sets of plants.

Now, I’ve got to get me some Baccharis pilularis!

ETA: Apologies for being California-centric here, but we don’t know of any research studies on native plant hedgerows in other places. However, be sure to check out this Mother Earth News article about living fences, which we’ve posted about before.

ETA 2: From our comments: check out the region-specific guidelines for plants which support pollinating insects, put together by the good folks at the Xerces Society.

The Barrier Method

Over the years we’ve lost countless plants to digging, chewing, trampling and sucking critters, mammals and insects both. We finally got smart. It makes sense to invest a little extra time and money to protect your crops and your livestock with physical barriers.

This practice started sort of piecemeal around here, with us only exerting ourselves over particularly problem-prone situations. Nowadays protection is standard for every bed we plant, for our seed starting boxes, and often for new perennials in the ground. The result is peace of mind, better results…and fewer gardening meltdowns from Erik (Squash Baby excepted).

We’ve written about all this before in various posts, but here’s some photos to give you an overview of some of the possibilities:

Our seedling trays are now contained within The Germinator ™: a large screened box. Prior to this invention, we arched chicken wire over our seedling trays to keep squirrels and loose chickens out.

All of our beds, whether raised or in the ground, are spanned with arches of wire which hold up aviary netting. The netting is held down around the edges with a variety of anchors, anything from bricks and boards to U shaped wire stakes. This keeps critters like digging skunks and birds out–but not insects.

Sometimes we cover our veg beds with a very light floating row cover (Agribon 15) instead of aviary netting. This not only keeps out critters, but also blocks many insects, particularly the cabbage worms that harass our brassica crops. It’s not pretty, but it keeps the plants pretty within. Heavier gauges of row covering can be used to ward off frost, or help jump start plants in cold weather.
Our chickens have a very secure coop. Connected to it is some extra play space, bounded by picket fence. This doesn’t protect the chickens from much, but they only use it during the day, when predators are few. It’s more to protect our garden from them. But I hope you can see the twine that stretches from picket to picket. These discourage the hens from flapping out of their run, and keeps hawks from swooping down on them.
We often protect newly planted perennials with circles of chicken wire staked to the ground. This young berry is protected from anything digging it up or stepping on it.  If I wanted to make sure critters couldn’t nibble on it, I’d pinch the top closed as well.

Genetically Modified Oranges Coming to a Store Near You

The ACP via UC Riverside

A tiny insect known as the Asian Citrus Psyllid (ACP for short) spreads a incurable bacterial citrus disease known as huanglongbing (HLB) or “greening.” Once a tree is infected with HLB there is no cure–you have to cut down the tree. HLB and a host of other problems, including thousand of acres of abandoned citrus groves, have devastated the Florida citrus industry. The psyllid made its way to California and the industry here is alarmed that HLB will soon follow. A Reuters story on HLB, “A day without genetically altered orange juice” has a number of astonishing revelations,

The bacterium that causes citrus greening is so lethal that the U.S. government classified it among potential bioterror tools known as “select agents” until about two years ago, severely limiting the scientific community’s ability to conduct research into the organism.

Yet another example of terrorism fears getting in the way of common sense.

The Reuters story goes on to discuss the development of genetically modified orange varieties resistant to the disease. Calvin Arnold, Laboratory Director of the U.S. Horticultural Research Laboratory in Fort Pierce, Florida, reacting to possible consumer push back on the issue of GMO oranges, suggests,

I think especially here in the U.S., they’re understanding transgenics a lot better. Just like people go to Taco Bell, they know they’re eating crops that have been produced transgenically,” Arnold said.

I try to stay open minded about GMO. It may indeed be the case that if we want either bananas or oranges we may have to resort to GMO. But I think our energies might be better spent on preventative pest management strategies. Our large scale agricultural system leaves us vulnerable to unexpected “black swan” events like HLB, colony collapse disorder and SARS. We may enjoy the efficiencies that come with globalization and huge monocultures, but Mother Nature doesn’t work that way, and she will, ultimately, defeat our intentions with tragic results. A more biodiverse and distributed agricultural system with far less international and interstate shipment of goods is less vulnerable. It’s too late to deal with HLB this way, but perhaps we can head off other catastrophes. In the end, more of us will have to to plant our own vegetable gardens and run small farms.

A last, ironic tidbit in that Reuter’s story–for a disease whose spread was facilitated by globalization–some of the labor intensive research necessary to deal with HLB is being . . . outsourced to China.

What’s eating my cilantro?

Mrs. Homegrown here:

While we’re inviting questions, we’ve also got a question for you guys. What sort of critter likes to eat cilantro? I think it’s a critter, not a bug. There’s no sign of leaf damage, just nibbling the stems down. There’s no digging or other disturbance.

Whatever this critter is, it has a defined taste for cilantro, because the cilantro is interplanted with parsley and it never so much as touches the parsley, or anything else in the garden, for that matter. It just comes out at night and decimates the poor cilantro.

Bagrada, The Bad News Bug


Homegrown Neighbor here:

I’ve been busy in the garden lately and one of the reasons I’m so busy is that I’m battling a new pest, the bagrada bug (Bagrada hilaris). This new pest made its way to the U.S. recently. It was first found in L.A. County in June 2008. So far in the United States it is only in Southern California and in parts of Arizona. If you live in a northern climate, hopefully you will be spared the spread of this heat loving pest.

I tend a garden in one of L.A.’s hottest microclimates. Even when the mercury is over 100, bagrada bugs seem to do just fine. And unfortunately they love a lot of our favorite garden vegetables such as broccoli, kale and cauliflower. The local nursery says they are destroying the allysum as well. In my garden they have been particularly devastating to an heirloom broccoli raab and some wild arugula. They also are munching the caper plants. Actually, they don’t munch, rather they suck juices out of a plant.

The nymphs are small and resemble a ladybug. Mature bagradas are black with orange markings and look like a beetle. They are often seen in mating pairs. They reproduce quickly and lay their eggs in the soil. Apparently insecticidal soap can help control them but, because they are so new to the U.S., little is known about their ecology here.

I hope some natural predators show up on the scene soon!

I’m trying to control them with diatomaceous earth, soap sprays and organic insecticidal oils. But I’m being really careful about the soaps and oils to be mindful of the bees in my garden.

I think that one of the keys to being a good organic gardener is observation. So I’ve just been watching the bugs, trying to handpick them and wash them off. Diatomaceous earth doesn’t affect the bees, so that is a good thing. It seems to help at least. But after a few days of no beetles, the population seems to explode again. When the populations get too big I’ve been spraying with neem. But I never spray near the flowers that the bees like the best. So it’s quite a challenge, since the bees are all over. I’ve decided to try to spray only after dark now, when the bees have gone to bed.

UC Riverside Center for Invasive Species Research fact sheet on bagrada can be found here.

Mr. Homegrown here: I found one peer reviewed study related to Bagrada hilaris controls, which you can access here.  The study found that the most effective treatment is the systemic pesticide imidicloprid which, unfortunately, is also deadly to pollinating insects and is a substance I don’t believe should be on the market. The study did show that starting plants at a cooler point in the season reduced heat loving bagrada bug numbers substantially. Confusingly, Bagrada hilaris is sometimes referred to as the “harlequin bug” which is also the popular name for a similar insect Murgantia histrionica.

Playin’ Possum

Since it happened too fast to take a picture I offer, thanks to the interwebs, this image of former Secretary of State of Florida Katherine Harris holding an opossum.

When I stepped out into the backyard early this morning to let the chickens out, I found an opossum just outside the coop eyin’ my ladies. It ran off well before I got anywhere near the coop. Since our dog passed on I’ve noticed an uptick in backyard critters. Still, it was late for a possum to be out–perhaps it had been partying down on nearby Sunset Boulevard and was just getting around to finding some grub. And that grub? Like us, opossums eat both eggs and chickens.

As with all such pest problems I went straight to the University of California integrated pest management website where I found a helpful article on opossums. The advice:

  • Pick up fallen fruit (I’m pretty good about this).
  • Eliminate wood piles (I’ve got one I need to eliminate).
  • Don’t leave pet food outside (I never do this, though I had forgotten about a mostly empty bag of chicken feed that the opossum could have been attracted to).
  • Screen off building entrances (I’ve done this).
  • Sit out on the back porch with a rifle. As UC puts it, “opossum may be spotlighted at night and shot”  where, “it is legal and safe to do so”  (can I employ our local gang?)

Habitat control is a great way to keep the population of critters like opossums at manageable levels. But there’s a problem here for those of us in urban or suburban areas. I could do all of these things (minus the gunplay) but what if several neighbors on my block have fallen fruit, outdoor pet food, and open basements?

What we need is an integrated pest management version of Neighborhood Watch, a group of people, at the block level, who would help folks reduce pests without resorting to pesticides and poisons. Sadly, I have no idea how to organize such a thing without coming off as arrogant and overbearing. But when we, at the neighborhood level, figure out how to make these sorts of arrangements that benefit the common good we’ll be well on our way to a more perfected humanity.

Wait, I got it, a neighborhood possum roast!

An earlier version of this post contained the phrase “paryting with the winos and tranny hookers down on Sunset . . .” A number of readers, quite rightly, took offence at the word “tranny.” My apologies to anyone who may have been offended. 

Asian Citrus Psyllid Eradication Program Causes Outbreak of Citrus Leafminer

Florida citrus farmers have been blanketing their orchards with pesticides in an attempt to eliminate the Asian Citrus Psyllid, an insect that caries a fatal citrus disease. But the campaign has had unintended consequences, namely the eradication of the natural predators of another citrus pest, the leafminer. According to the USDA Agricultural Research Service,

“The leafminer moth, Phyllocnistis citrella, forms channels as it feeds inside citrus leaves and, as a result, often makes the plant more susceptible to canker disease. Further exacerbating the leafminer problem is the spraying of more insecticide to combat another pest—the Asian citrus psyllid. The insecticide is killing off the leafminers’ natural enemies, allowing the pest to increase in numbers.”

The moral, in my opinion, is the same for both nature and the economy: don’t tinker with complex systems and avoid putting all your eggs in one basket, i.e. crop monocultures. Doing so is asking for “black swans” and catastrophic failure. As Nassim Taleb says, “counter-balance complexity with simplicity.” The race to layer insecticides on top of insecticides and then search for pheromonal solutions is too complex for my taste.

Italy Questions Neonicotinoid Pesticides, California Department of Food and Agriculture Loves Them

Can I report the CDFA as a pest?

Responding to concerns about the safety of nicotine based pesticides, such as imidacloprid, the Italian government, last year, banned them as a seed treatment. According to the Institute of Science in Society, Researchers with the National Institute of Beekeeping in Bologna, Italy discovered that “pollen obtained from seeds dressed with imidacloprid contains significant levels of the insecticide, and suggested that the polluted pollen was one of the main causes of honeybee colony collapse.”[1] Since the Italian government’s ban last year bee colonies have sprung back. In some regions no hives have been lost at all with the exception of citrus groves in Southern Italy where neonicotinoids were sprayed.[2]

Which brings me to the California Department of Food and Agriculture, whose love for the neonicotinoid pesticide imidacloprid I got to experience first hand. Last year our neighborhood was one of the first targeted by the CDFA for treatment in Los Angeles county after the appearance of the dreaded Asian Citrus Psyllid, a carrier of a fatal citrus disease called Huanglongbing (HLB)–see my early post about the psyllid and HLB. During a brief treatment period last fall CDFA agents and their contractors TruGreen attempted to spray every citrus tree with Bayer Crop Science’s version of imidacloprid, brand name Merit. During that spraying in my neighborhood CDFA agents and TruGreen:

1. Entered private property without warrants or permission.

2. Left misleading notices (click on image at right to enlarge) which failed to note that the treatment was voluntary.

3. Acted in an arrogant, condescending and rude manner. They also lied. When I declined treatment and noted that I was particularly concerned about the use of imidacloprid one agent offered what he called, “an alternative.” Upon further questioning he admitted that the “alternative” was a pellet version of imidacloprid–not an alternative at all, just the same insect neurotoxin in another form.

4. Ran out of pesticide. There are so many citrus trees in our neighborhood that the CDFA ran out of their precious imidacloprid tablets. They never returned to finish the job leading me to conclude that the operation was a kind of pesticide theater, a way to both justify their funding and please their friends at Sunkist.

European beekeepers would like to see all neonicotinoids banned for good. I’d like to see the same here. While imidacloprid is probably not hazardous to humans, all the oranges in the world are not worth killing our pollinating insects. And fighting invasive species this way is a losing game. I believe that HLB is inevitable. It’s just like Pierce’s disease in grapes, which is now an unavoidable part of viticulture in Southern California.

To my neighbors: I suggest we organize. Let’s resist CDFA’s attempt to spray more imidacloprid should they come around again. I’ve created a form where you can leave your email address here. I promise not to share the email addresses you provide or to send out spam. The list I create will only be used in the event we need to organize as concerned citizens. Hopefully I’ll never have to send out an email. But let’s not let CDFA treat us in a rude or condescending manner again. The next time CDFA pays a visit they may come with warrants and be even more surly. I’d love it if we had a crowd to greet them.

Nutria Trappin’ by Bike!

I like to keep up on all the “urban homesteading” trends, but bikesnobnyc beat me to this one: nutria (Myocastor coypus) trapping via bike.

“We then returned with our catch and skinned them, prepared the hides for tanning and butchered the carcass and cooked up a bit of the meat. Most folks seemed pleasantly surprised at the “chicken- like” taste of the meat.”

Read more about it at dellerdesigns.blogspot.com, “Maker of Fine Hats for Town and Country Cyclists.”

The Skunk Whisperer

Normally I ignore the business related facebook pleas filling up the Homegrown Evolution in box, but one came today that I had to grant some free publicity. We’ve all heard of horse whisperers and TV’s dog whisperer. You may have even heard of the chicken whisperer. Step aside for the . . . skunk whisperer, a “no-kill, no-trap” pest control company based in Oklahoma which seems to consist of at least two skunk whisperers, each with their own cartoon avatar and territory.

From what I can tell from the Skunk Whisperer’s website, www.totalwildlifecontrol.com, they seem to practice a common sense integrated pest management (IPM) approach to critter control. In other words, work first on eliminating habitat. Studies have shown that if you trap and try to relocate animals such as skunks and raccoons, you’re just making room for a another one to take their place. If you poison them you risk killing predators up the food chain, not to mention pets and humans. And poisoned mammals have a nasty tendency to crawl into a wall to die leaving a stench that lasts for months.

As a chicken owner I’m sensitive to the raccoon menace. Following the IPM approach, just like the Skunk Whisperer, I made sure the chicken coop was well fortified and I got rid of a water feature that was a nightly raccoon attractant. Our Doberman is the icing on the anti-raccoon cake.

It’s easy to see how preventing points of entry into our homes is one important part of fending off critters. Judging from the voluminous photos on the Skunk Whisperer’s facebook page they focus on screening out critter access. The beehive relocation I helped with recently and the one I’m going to do in the spring are both because hives made their way into buildings with gaps in the woodwork. Close up the gaps and you exclude most non Homo sapiens. And can we please stop leaving pet food outside?

Possum whispering and bare handed trappin’.

It turns out that the Skunk Whisperer also uses a technique I just tried. The contractor who did our foundation work left the crawlspace access door open. I’m pretty sure something took up residence down there. If I just closed the access door I risked having a critter die under the house, or possibly killing someone’s cat. Instead, I got a cheap raccoon-sized trap and rigged it up as a one-way door. Critters can exit, but they can’t come back in. It seemed to work–the trap sprung and something either left or tried to get in and couldn’t. Now I can close off the access door and not worry about the scent of death wafting up through the house. Here’s what my skunk trap-out looks like–excuse the bad picture and remember that it’s not a trap as the exit end is always open:

I cut a board to fit around the trap-out and nailed it to the corners of the crawl space opening.

The next step is to get a cartoon of myself and I’ll be making the big money.

Here’s the Skunk Whisperer removing the Pepsi machine raccoons. As he put it, “They’d put money in and a raccoon hand would come out.”