Fooling some of the people all of the time

My email has brought me some interesting news relating to neonicotinoid insecticides. I received a message from the Friends of Newton Cemetery announcing that they’re creating a pollinator garden with a grant from Bayer. The cemetery is a beautiful park, generously open to the public. I wondered whether its horticultural staff knew that their garden to provide forage for pollinators was to be funded by one of the world’s top manufacturers and sellers of pollinator-killing neonics.

Newton Cemetery October 2017

    Bayer makes the best-selling neonic, imidacloprid, sold as Admire, Advantage, Confidor, Gaucho, Merit, Hachikusan, Kohinor, Premise, Prothor, and Winner. 

Merit

They also sell two other successful neonics, clothianidin and thiacloprid. Despite mounting scientific evidence, Bayer has consistently denied that neonics harm pollinators, including bees. They blame other factors, such as varroa mites, for the bee die-off. Their Bee Care Program and the entity that made the grant to Newton Cemetery, FeedABee, seem to be part of a campaign to combat negative publicity for Bayer’s insecticide products. Viewed in this light, the gift to the cemetery seems less community spirited.

How dumb do they think we are?

    But a pollinator garden is a good thing. I don’t see why the cemetery can’t accept Bayer’s money for an environmentally positive project. They just shouldn’t use it to buy plants treated with Bayer’s products, or other neonics. The insecticides persist for years in treated plants. Bees that contact them die or suffer neurological damage. 

Neonics can kill whole colonies or do more subtle harm

    I wrote back to the Friends of Newton Cemetery to ask whether they’ve found a source of reliably neonic-free annuals and perennials. In my experience, this has been a difficult quest, but a necessary one. Who wants a pollinator garden that kills pollinators?

I grew these marigolds from organic seed, so I know they won't kill bees

    Meanwhile, there’s some good news on the horizon about neonics. The Massachusetts legislature is considering a bill to ban the direct sale of the insecticides to consumers in our state. I was delighted to hear from my state senator, Cynthia Creem, that she cosponsored the bill, H4041, An Act to protect Massachusetts pollinators. Since the EPA hasn’t banned neonics, it’s up to the states to take action.

    Even if neonics aren’t sold directly to consumers, though, they’ll still affect insects in our gardens as long as garden centers and big box stores sell treated plants. Plant production is a global business. Wholesale nurseries source seeds all over the world. They buy tiny annual seedlings from rooting stations around the US and tissue culture products imported from as far afield as South Africa, Holland, Turkey, and Poland (tissue culture converts tiny pieces of plant tissue into large numbers of genetically identical plantlets). Giant plantations in Costa Rica and Ecuador send cuttings of perennials for US wholesalers to root and grow to saleable size.

The annuals we buy are international travelers

    As long as plants can be treated with neonics at any of these stops on their way to market, gardeners still risk exposing pollinators to the dangers of these chemicals. Home Depot has promised that its plants will be free of neonics by the end of 2018. It’s a start.

Summer singers

In August’s heat and humidity, my gardening activity is down to watering my container plants and occasionally deadheading. 

Growing vegetables on the deck

For someone choosing flowers to accommodate bugs, I don’t know enough about the insects, their lives and habits. This seems like a good time to learn about a few. I started with the singers of the late summer chorus that fills the air from this month into fall. 

    I learned that most of what we’re hearing is crickets, katydids, and cicadas. I picture a cricket as a chunky black insect shaped like a grasshopper. Those are the field crickets. 

Field cricket, genus Gryllus

In addition to their chirps, the background trill or hum we’re hearing at night comes from tree crickets, which look quite different.

Snowy tree cricket, Oecanthus fultoni

    As you might guess, it’s the male crickets that make the noise. They have three kinds of songs, a loud one for attracting females, a softer one for wooing a potential mate once she’s nearby, and an aggressive one for warning off other males. 

     Crickets and katydids make their sounds not with their mouths but with their wings in a process called stridulation. They rub one wing across a rough patch on the other, similar to running a finger down the teeth of a comb. The shape of the wings amplifies the sound. Females are looking for larger mates, and the male crickets can improve their chances by moving their wings faster, which makes them sound larger.

    It’s true you can gauge the temperature by timing chirps of the snowy tree cricket. The number of chirps counted in 14 seconds plus 40 equals the ambient temperature. I find it sad to hear slowing chirps in late fall as the last crickets get too cold to sing.

    Katydids get their common name from their song, which some listeners think sounds like “Katy did, Katy didn’t.” They make a buzz, “zip” or “zeep” sound. They look like large green grasshoppers with long antennae. They have ears at the joints of their long front legs.

Common true katydid, Pterophylla camellifolia-photo Lang Elliott

     

     Crickets and katydids don’t harm our plants. They eat small bits of plant material without doing noticeable damage. They may function as beneficials, eating insect eggs, larvae, or small insects such as aphids or scale insects (I’ll be glad to share as many of those as they want!).

    The most dramatic of the singing insect trio is the cicada, which makes a distinctive crescendo “zee-oo-zee-oo” lasting 15 to 30 seconds. These songs can be as loud as 120 decibels, painful for human ears. The males sing for mates by puffing out their abdomens and bending flexible ribs on parts called tymbals. Adults suck sap from woody plants, but without doing much harm.

Annual cicada, Neogtibecen linne

    This is the insect that drops its nymphs to the ground, where they burrow under and feed on root sap. Annual cicadas emerge the next spring. Periodic cicadas emerge together on 13- or 17-year cycles.

17-year cicada, genus Magicicada

    These interesting insects add to the late summer ambience without doing anything gardeners need to worry about. Nice to know.

Living fossil returns home

I first saw dawn redwoods (Metasequoia glyptostroboides) in 1995 when I was taking a course in identifying trees at the Arnold Arboretum. Entering the arboretum’s main gate, visitors come upon a grove of these magical trees growing beside a stream. When I had a chance to plant new trees two years later, there was no question but this would be one of them.

Dawn redwood in May, Willow Pond, Mt. Auburn Cemetery

    This species has an intriguing history. It was found in fossils dating back 165 million years to the Mesozoic era but was thought to have gone extinct at least 5 million years ago. In the early 1940s, Chinese scientists found living specimens in a remote area in Sichuan and Hubei provinces in southwest China. They communicated with colleagues in the U.S. and sent seeds to the Arnold Arboretum, whose director at the time, E.D. Merrill, distributed them to botanical gardens and arboreta around the world. These seeds grew readily in a wide range of conditions, and dawn redwoods became popular ornamental trees.

Dawn redwoods in fall at Wisley Gardens, Surrey-ukgardenphotos

    The stand of trees discovered in the 1940s, revered locally under the name of “water fir,” is now down to about 5,000 trees, having lost ground to conversion of the area to rice paddies. Fully grown trees can live to 265 years, reach trunk diameters of 7 feet, and grow as tall as 165 feet. The trees are legally protected, but all the cones are scooped up by people who want to try growing their own dawn redwoods. There’s no sign that the mature trees are reproducing anymore, so the international diaspora may be the only hope for survival of the species.

    Our dawn redwood came to us at about five feet tall. It’s since grown to at least forty feet high with a trunk 16 inches wide. The trunk is already showing the distinctive buttressing that gives the species some of its fairytale quality. 

Our dawn redwood has grown fast

The ferny leaves are soft, not like most waxy conifer needles. They begin the year a bright lime green and turn a rusty orange in fall before falling.

Soft, ferny leaves

    Dawn redwood is one of the few deciduous conifers, a group that includes bald cypress (Taxodium distichum), larch (Larix spp), and golden larch (Pseudolarix amabilis). 

Golden larch about to shed its leaves

Why deciduous? Apparently dawn redwoods grew so far north in Canada during a warm period in the earth’s history that they experienced polar light conditions: three months of unceasing sun in summer and total darkness in winter. They adapted by evolving from evergreen to deciduous.

Dawn redwood at Arnold Arboretum in winter-photo Glasser

    I like knowing that this tree was once common in my area—back when the dinosaurs roamed the earth, literally. This points out the complexity of defining native plants. Enthusiasts usually think of natives as plants that grew in North America before European settlement. But the moment Europeans set foot on our soil with foreign seeds stuck to their shoes is only a brief snapshot in the botanical history of the continent. I can rightly say that by planting a dawn redwood, I reintroduced a New England native.

 

Neonics' notoriety

Evidence keeps piling up against widespread use of neonicotinoid insecticides. Reacting to a critical review by its scientific branch, the European Union recently banned the use of the chemicals except in closed greenhouses.

Neonics harm bumblebees

Some of the bad news:
•    Populations not just of honeybees, but also bumblebees and solitary bees, important pollinators, are declining in many countries where neonics are widely used. If they don’t die, exposed bees have fewer queens and may be neurologically impaired, losing their navigational ability.
•    Neonics are found in water, soil, and wildflowers near fields of treated crops. Insects can contact the pesticides without visiting the crop plants.
•    Three out of four honey samples from around the world and 86 percent in North America contained neonicotinoids.
•    Neonics have been found in food, and claims that they’re harmless to vertebrates are losing conviction; for example, exposed sparrows lost weight and got lost during migration.

This swallowtail caterpillar's food could be contaminated

As with climate change, the science is complicated, and the pesticide industry is still saying there isn’t enough evidence that neonics are causing the bee die-off. An alarm sounded when a German study showed a 75 percent decrease in flying insects over a 25-year period, but this wasn’t attributed to neonics alone. Analysts opined that habitat loss and widespread use of pesticides were both major determinants. In the US, it’s thought that neonics may weaken insects’ immune systems, making them susceptible to epidemics caused by fungi and mites.

Honeybee on a black-eyed Susan

    What’s to be done? New systemic pesticides are already being introduced, but that hardly seems like a solution. Farmers in the UK objected to the European Union’s ban, saying the pests they needed chemicals for are still around. I hope farmers will transition toward methods that minimize pesticides and preserve insect habitat.

    On my tiny scale, I’m still trying to keep neonics out of my garden but recognize that I’m not fully succeeding. I bought only untreated seed this year—treated seed is the way neonics are often introduced into the commercial growing process, and they persist in tissues as the plants grow. My favorite garden center promises that they don’t use pesticides, but does that mean their plants are neonic free throughout the life cycle? In today’s nursery trade, seedlings change hands repeatedly.

I can't be certain this 5-year-old caryopteris is neonic-free

    I’ve fallen back on reproducing my own plants by spreading seed or making cuttings or divisions.  I got a new generation of purple coneflowers (Echinacea purpurea) by cutting off the flower heads of some organically grown plants in fall and scattering them in an area where I wanted more plants. Two years later, many new coneflowers are blooming.

Purple coneflowers are popular with bees

    To make my new bed, I dug out and transplanted wedges or whole offspring from existing perennials: variegated iris (Iris pallida), columbines (Aquilegia spp), dwarf goat’s beard (Aruncus aethusifolium), and goldenrod (Solidago spp). I’m growing some new bearberry (Arctostaphylos uva-ursi) from cuttings.

This hoverfly is another hardworking pollinator at risk

    Making new stock from my yard’s plants would exclude pesticides if I’m right that the plants started out untreated, but if not, I’m just perpetuating contamination.