Garden Visitors

Make new friends, but keep the old; one is silver, the other gold. Old friends, I'm assuming, are golden, new ones silvery.

We've had both kinds in the yard in recent months: recurring visitors I expect to see each year and would worry about if they did not show up, as well as unexpected sightings of life forms I may have heard about -- or not -- but haven't personally encountered in our garden.

One old friend, seen last April, was truly golden:

The golden tortoise beetle makes infrequent appearances; only once or twice before have I come upon one. Evidently they like to chew on members of the morning glory family, such as the ubiquitous and ineradicable bindweed, so be assured that this year's little fellow is finding plenty to eat. It's said they will change color when disturbed, shifting from shiny metallic gold to a flat orange with spots to fool predators who know how tasty they are but will avoid unpalatable but similarly shaped lady bugs. I guess this bug trusted me, as he stayed shiny on my palm.

I don't think I would worry if the golden tortoise beetle did not appear one year; but I would greatly miss his cousin, the lady bug, scourge of aphids and other bothersome guests. Fortunately, lady bugs seem to like our garden and are regular patrons. I've heard that they are attracted by brassicas and it's true that in the spring of 2015, when we had an especially abundant crop of broccoli, two beds worth, plus another bed of kale nearby, we also saw an explosion of the lady bug population. They were everywhere; I had to brush myself off before coming into the house. This year is back to normal with fewer brassicas and only occasional bug sightings, such as, in early July, a lone lady resting on some lady-like Queen Anne's Lace.

Another strikingly patterned orange and black visitor, the notorious harlequin beetle, has been appearing in the last couple of years in early spring. It also seems drawn by brassicas, especially the cover crop mustards I started planting in the same time period. Although it has a bad reputation for sipping juices out of a wide range of garden plants, dining on stems and leaves as well as fruit, weakening and discoloring plant tissues as it goes, I haven't noticed a lot of damage beyond a few holes in the mustard leaves.

What to say about a new bug found this year in the dried up, two-year-old fava bean pods, saved for cover cropping? In late March, when I dug into the bag of old pods and started shelling out the beans, I noticed some little beetles scurrying for cover. I also noticed lots of little holes dug into the fat tawny seeds.

One of the pods yielded up a pale, translucent, tiny worm, no doubt the larval form of this new insect.

It did not take much searching online to identify these bugs as broad bean weevils, a type of beetle and member of a family of weevily critters who feed on dried legumes and grains. The adults lay their eggs on the surface of pods or seeds, then the larva burrows down into the seed and consumes what it needs before pupating in place. The hatched adult crawls out of the little seed tunnel hollowed out by the larva and the beat goes on.

The bugs were indeed feasting on my fava bean seeds, but as everything I planted sprouted and grew without problems, I nonetheless count them as new and interesting friends.

Old or new, silver or gold, it's always a treat to encounter the many varieties of life forms that abound in our backyard abundance.

Nitrogen Fixing Nodules

The fava bean forest got cleared out today to make room for tomatoes. When I pulled up the towering plants I was glad to see that the root clumps are festooned with clusters of nitrogen-fixing nodules. That means that these fava plants, like all hard-working legumes, invoked their magical powers of pulling nitrogen out of the air and storing it in tiny sacs strung along the root systems.

Actually, the whole story is more complicated. The fava roots exude sugars into the soil to attract a particular type of bacteria which attach themselves to the roots. These bacteria are able to convert nitrogen from the air into a form that the plant can use. What the plant can't use right away is stored in the nodules. (I don't really understand this part. How does the nitrogen get to the bacteria way down on the roots?)






Here are the sturdy stalks and root clumps ready for the compost pile. If I were able to leave all this material in the bed and dig it under so it could break down right in place, the nodules would enrich the soil with their stored nitrogen.

Also, if I had dug in the plants before they formed their ample harvest of beans, there would have been lots more stored nitrogen and lots more enrichment. Unfortunately, none of these "ifs" are going to benefit the tomato seedlings which need to go into this bed right away.

But the extra nitrogen won't go to waste and will eventually make its way back to the garden as compost.

Meanwhile, here's a link to a great little video where a couple of enthusiastic agricultural scientists explain nitrogen fixation on soybeans. After listening to these guys, you just can't help rooting for roots! Yay roots!

Fava Bean Eco-System

The fava beans are reaching out for the sky with their graceful fans of leaves and elegant blossoms with black accents. Two adjacent beds of seedlings from Cottage Garden Nursery, which were planted out last fall on October 3, are now eight feet and over -- even subtracting the ten inch height of the beds.






The towering stalks form a little forest eco-system all their own, with some volunteer chard sheltering on the shady forest floor layer, most of the blossoms and maturing beans in the understory, and the tenderest new leaves -- so good in salads -- forming the canopy.






Here are the understory beans, starting to size up.






The understory seems to be very popular with all manner of insects -- such as this Common Darter Dragonfly. (Nothing common about it; it's the only one I've ever seen in this garden, which is swarming with dragonflies. I had to do some Web sleuthing to find out what it's called.)







Another mystery insect I was not able to identify: these weird beetles with dramatic African-shield-like markings. Dozens of them can be found scurrying at eye level among the stalks and leaves in the morning sun.






And here's the first sighting of the hornet queen, from March 6. She too seems to favor the mid-level fava forest.






It was almost reassuring to find a common, everyday, garden-variety ladybug sunning herself on a leaf.






And a regular honeybee browsing the blossoms.

B. sometimes wonders why I grow favas at all, because we have only managed to make a meal of them once. I don't dig them under as a cover crop before they form beans, which is the most efficient use of favas as soil enrichment. I let them go full cycle with a fine full crop of fat pods but then get overwhelmed and can't follow through with the laborious processing required to extract the delicate gourmet beans. As I said, that happened once.

I guess I grow them just to watch the show. Well worth it.