Varroa Bee Mite

Here’s an inspiring sight from a hike last year: a non-native honeybee pollinating native ko'oko'olau flowers along Chain of Craters Road in Hawai'i Volcanoes National Park. Makes me ponder the roles of honeybees in our native ecosystems and how they will be impacted by the recent arrival of the varroa bee mite.

Until recently, Hawai'i and Australia were the last places in the world that were still free of the varroa mite, which feeds only on honeybees and destroys entire colonies. However, the varroa mite is now widespread on O'ahu, and last month the Hawai'i Department of Agriculture recorded the first sightings on Hawai'i Island. So far there’s been no detection on Maui, Kaua'i and Moloka'i.


A varroa mite is very tiny, only 1-1.5 mm, but magnified under a hand lens it sort of looks like some weird Pokeman character, a freaky, hairy, flattened reddish-brown jelly bean with legs. Small populations have been discovered on feral bees in the Hilo area in five locations, according to Clayton Nagata, plant quarantine inspector with the HDOA. At the Kino'ole Farmers Market this weekend, Nagata talked to the public about the HDOA’s efforts to control the spread of the varroa mite. They're using swarm traps made from pressed paper pots baited with beeswax and pheromone. So far there are 150 traps placed within a one-mile radius of where the mites were first found near the Hilo Airport.

Some locations where the varroa mite has appeared:

• Near Hilo Airport, by Verna’s plate lunch stand and Hilo Seaside Hotel
• Banyan Golf Course
• Along Kamehameha Avenue, near Suisan
• Near the Waiakea Fire Station, old refueling depot in Keaukaha

Only 8 to 12 individual varroa mites have appeared in each wild colony. If the Big Island becomes heavily infested it could be devastating for local beekeepers and fruit growers who depend on these important pollinators. A reduced bee population means local farmers and gardeners would see poor yields and low quality produce. In addition, the varroa mite is bad news for the local industry in Kona that raises millions of queen bees for export to agricultural ventures worldwide; the cost of buying honeybees to release in nurseries would most certainly increase. And what will be the impact on the cost of food?

If you are reading this and you are a honeybee, stay away from airports. The HDOA is trying to establish a honeybee-free zone around airports, and unfortunately, to find out if a hive is infested with the mite the HDOA has to kill the entire colony. The HDOA doesn’t know to what extent the varroa mite has spread on the Big Island.

There is a way to partially eliminate the mite from a commercial hive by using a sticky tape with a miticide; it touches the bees and kills the mites, but this doesn’t help our producers of organic honey.

If you see honeybees or beekeeping equipment being moved between islands, or on the slim chance you are one of the few sharp-eyed gardeners who like seeing bees up close and personal (certainly not me, I’m allergic) and you see what you think is a varroa mite, contact the HDOA at (808) 643-PEST (7378).

Learn more about the varroa mite from the HDOA website here and here. Download a HDOA PDF publication on the varroa mite here.

Sustainability at 3500 Feet

When it comes to experimentation with native plants in gardening, Bonnie Goddell, proprietor of Volcano Guest House, is enthusiastic and fearless. Around the perimeter of her huge duck pond in Volcano at 3500 feet she has planted native Hawaiian plants normally seen only at sea level wetlands, and they’re thriving suprisingly well.

'Ae 'ae, (Bacopa monnieri) or water hyssop, an indigenous Hawaiian plant also used in Ayurvedic medicine, is spreading along the edges of the pond, as is makaloa, 'uki'uki and other native sedges.

The pond and landscaping around it are only about a year old, but it looks like it’s off to a great start. Bonnie’s goal is to create an eco-friendly, agriculturally productive aqua-farm – it’s stocked with tilapia and koi, and yes, the ducks are for consumption.

The biggest surprise was a native sedge I'd never seen before. It looks like a giant green onion, and Bonnie says it's quite aggressive around her pond, so much so she’s had to cut it back several times. It's a very handsome specimen indeed, and I'm wondering how it would do in other island water gardens.

I could be wrong, but I don't think these lowland wetland natives naturally occur at this elevation. It will be interesting to see how they perform in a manmade system within the surrounding mauka native rainforest ecosystems. So far it's quite impressive.

Lichen Limerick

Plant geek poetry, courtesy of Honopua Farm.

Whee-ha, Waimea

I always pick up lots of tips and ideas at farmers markets, so I couldn’t resist stopping by the Hawaiian Homestead one in Waimea. Growers here take advantage of cooler upland conditions to raise all kinds of ornamentals and edibles that lowlanders like me only dream of, so I knew I’d be in for a real adventure on this unscheduled side trip on the way to Kona.


Tootsie Weller of the Burdon family is the guiding force behind Ainahua Florals, a family-run business on Hawaiian Homestead farm lots in Waimea. Their artful, Hawaii-style flower arrangements are mainly composed of locally grown flowers. I couldn’t believe the freshness of the plant material and the creative combinations of bright colors and complementary textures. Pure eye candy!

A few booths down I was allured by the scent of lavender at the booth of Ken and Roen Hufford of Honopua Farm. “Look at your feet,” said the amiable fellow there, greeting me with a big, easy smile. “You’re stepping on it.” Sure enough, a layer of lavender cuttings lay on the ground beneath my sandals, the leaves blackened from being trodden on all day by a steady stream of patrons. “That’s our herbal chum – or herbal palu, as we call it in Hawai’i. Draws in the big fish,” he said, revealing one of the tricks of their trade. As if that weren’t enough, he brought out a sample of their pikake essence body mist with coconut oil base and sprayed a cooling shower around my neck. “It’s like wearing a pikake lei,” he declared. Of course, right then I was hooked – I convinced myself I couldn’t live without this heady indulgence and bought a bottle for $15.



Roen Hufford sat behind the tables laden with organic greens and other enticing comestibles. She told me her family has been growing organically and selling at the Hawaiian Homestead market for an impressive 16 years. The mild pink radishes they were selling on this day were a bonus crop of Asian radish called Hong Vit, which they grew mainly for the young tender greens because the leaves aren’t hairy like other radishes and they add a delightful spiciness to the Honopua Farm salad mix.

Right about now you might be stewing some lowlander envy of the kinds of plants upland gardeners of Waimea can grow. If it's any consolation, Roen told me a grower from Kea'au had packed up early that day because he had sold out of everything he brought, all the things that he can grow but Waimea people can't, like anthuriums and papayas.

Heading back to my car I saw some preserves from Eko Farm that looked quite yummy...



...and then I had a close encounter of the botanical kind – the kind made out of pantyhose, moss, and grass seed, and a really out-there puffy paint job. Take some of these babies home, add water, and in a few days you have an attack of the turf people of Waimea. Scary or tasty? You and your kitty can decide.

Native Water Garden

I rarely see a variety of Hawaii’s native plants being used for landscaping outside commercial buildings, so I was pleasantly surprised with the recently installed plantings outside Kawaiha’o Plaza, the administrative offices of Kamehameha Schools in downtown Honolulu. This multi-level raised planter seems to be designed as a miniature ahupua’a.

Mauka plants such as naupaka kahuahiwi, palapalai, and koa were planted at the top level...

Kalo was growing in a tiny lo'i at midheight along with native sedges...

Even 'ihi'ihi was there, an unusual endangered native fern that resembles a four-leaf clover. In the wild it grows in vernal pools, so naturally it's a good plant for the water garden...

At the very bottom were plantings of makai plants such as alula...

hala pepe and 'ae'ae...

As the landscaping matures it will be interesting to see how many of the plants will have to be removed or replaced, if any. The koa seemed planted too close to the building, and I was surprised to see the naupaka kuahiwi was still thriving even though it was at this low elevation. Nonetheless, I have much to learn from this landscaper -- I’m impressed! I’ll have to revisit in the future to check up on this very akamai and inspiring native water garden.

A Bittersweet Tale

Bittermelons look like what hedgehogs would be if they fell under a wizard's spell and became vegetables.

Once in a great while I like bittermelon Chinese-style with furu, fermented tofu. My Filipino neighbor loves bittermelon. Birds love his ripe bittermelon fruit and scatter the seeds, so occasionally I find vines growing in the middle of the lawn, which I mow anyway. However, now there's a bittermelon vine growing on the fence between me and my other Filipino neighbor. I'm sure neither of us planted it, but I'm not entirely sure if he's eating from it. He hasn't sprayed it, and usually he sprays the fenceline. It's actually my fence, so I guess I could just rip the vine out. But I don't want to spoil my neighbor's enjoyment, that is, in case he is in fact enjoying it. I suppose I could ask him, but he never answers the door when I go over.

So the vine just grows. Is it a weed? Some people would say if someone has found use for a plant, it isn't a weed. So I guess it isn't, because for me right now it serves as a reason to get to know my neighbor a bit better.

Half-Weed

Look! Is this Drymaria a half-dead or a half-alive weed?

Does limonene work as an herbicide? Two weeks after spraying I've decided the answer is yes...and no.

The label on the pesticide says that it is most effective on annual weeds shorter than 6 inches. I wanted to see what difference weed whacking would make before spraying, so I used a string trimmer to cut most of the weeds to ground level. I also left one patch uncut.

I found that the herbicide appeared to affect the foliage of some weeds that were whacked that weren’t affected when left intact. However, weed whacking before spraying didn’t seem to make any difference for hardier weeds. Limonene appeared to cause foliage to burn on some weeds but it didn’t outright kill them; the affected weeds put out new growth within 2 weeks.

For example, garden spurge greater than 6 inches that was sprayed looked healthy and unaffected, however buttonweed foliage burned though the stems seemed unharmed. Nutgrass sedge seemed to be unaffected by any of the treatments.



Limonene seemed to affect foliage of some weeds quickly. Oxalis turned yellow immediately upon spraying, as did Drymaria. I mowed sleeping grass (Mimosa pudica) in the lawn, then sprayed it; the weed and the grass surrounding it turned brown, but new growth appeared within 2 weeks.

Okay, so all of this is anecdotal and not so scientific, but you’ve read this far so you might as well read the rest of this half-baked report.

Unless someone convinces me otherwise, I’m not using limonene as a weed killer again. I’m sticking to my electric string trimmer and propane flamer for weeds that aren't kept in check with mulching and hand-pulling. Spraying limonene was a pleasant, fragrant exercise in weed abuse, but certainly not worth $21.99 as a weed control strategy. My conclusion: When life gives you lemons, don’t make weed killer.

De-lovely, De-weeds & D-limonene

A couple of weeks ago I happened to be wandering the “organic” aisle of my local hardware store, as I do every now and then to see what’s been added to the store’s inventory. In the past 6 years I’ve watched this section grow from one or two products to more than a dozen different ones filling half the length of the aisle, which I’d say is an indication of consumer demand. And on this most recent perusal I found something I’d never seen before: “organic” weed killer based on D-limonene, a citrus oil extracted from the rinds of oranges.

I’ve used other natural, earth-friendly limonene-based products: adhesive remover/solvent/degreaser, household cleaner, ant killer. Sounds like powerful stuff, doesn’t it? Since it’s OMRI-listed, of course it’ll be killing those weeds softly, shouldn’t it? However, if something says it’s “worryfree” I start getting skeptical. Is it safe, and does it work – really? I had to try it.

I usually pull weeds by hand or use a propane flamer to burn them. So a 32 oz bottle of concentrate for $21.99 nearly took my breath away – this is not cheap stuff, but then it wasn’t locked up like the Roundup was. On the way home I stopped to visit a friend. When I got back to my truck and opened the door, my sinuses were blasted with a familiar odor from small-kid time: Lemon Pledge. An oily scent, not entirely beckoning, like a crateful of Meyers with an industrial undertone. Apparently the bottle tipped, and even though the cashier had tightened it, it leaked into the plastic bag and a tiny bit spilled on the floor mat. Even a week later, each time my visiting niece got into my truck, she’d inhale deeply and sigh, “Mmm, auntie, your car smells so nice.” Not your typical reaction, but keep it out of reach of children anyway – read the label, there are some warnings.

The label says this weed killer takes care of “annual weeds” and that “perennial weeds may need more than one treatment.” I’m not sure what annual weeds are in Hawai'i though, since many plants perennialize here. When I bought the weed killer I did not know that even though it is a concentrate, 32 oz makes only 1 gallon of spray! I’ve decided that if this 70% D-limonene pesticide proves to be effective I’m going to use it only in areas next to the house where I don’t want to use flame.

Have a look at some of the weeds I’m trying it on.

(Warning: the following pictures may be disturbing to those with obsessive tendencies.)

garden spurge, koko kahiki, Chamaesyce hirta

Phyllanthus amarus

partridge pea; lauiki, Chamaecrista nictitans

bubble gum plant; root beer plant, Polygala paniculata

buttonweed (Spermacoce assurgens)

...plus oxalis and some assorted grasses and sedges.

Stay tuned for the results in the next couple of weeks!