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Archive for May, 2015

Asparagus beetle damage

Asparagus beetles cause mostly cosmetic damage

Asparagus beetles

The other day I had a call from a gardener who was having trouble with asparagus beetles chewing on his asparagus. These beetles don’t usually do a lot of damage but they can make the spears look a bit ragged especially at the tip. If not controlled, however, a heavy infestation of beetles and their larvae can cause defoliation of the asparagus ferns during the summer. This can weaken the plants and reduce spear production the following spring.

Asparagus beetle eggs and stem damage

Asparagus beetle eggs and stem damage

One of the worst parts about having asparagus beetles is that they lay their eggs all over the asparagus stems. These black cigar-shaped eggs are very prominent, sticking out at a right angle up and down the stalk like little prickers. Not very appetizing to say the least! If you have asparagus beetles, you will have the eggs and lots of them! There are two types of asparagus beetles in our area; the common asparagus beetle (Crioceris asparagi) and the spotted asparagus beetle (Crioceris duodecimpunctata).

Common asparagus beetle

Common asparagus beetle

Spotted asparagus beetle

Spotted asparagus beetle

Asparagus beetle eggs stick out from the stem. Damage to the stem from feeding is also evident.

Damage to the stem from feeding

The common asparagus beetle is the most prevalent and unfortunately is the one that does the most damage to the plant. Most of the time, unless there is a heavy infestation, the damage is purely cosmetic. The beetles feed on the stem leaving shallow grooves and scars on the surface. In some cases, the spears can become disfigured, ragged, and bent over like a shepherd’s crook. However, it’s the presence of those little black eggs sticking out all over the spears that is often the most objectionable part of an asparagus beetle invasion! Luckily, they are fairly easy to rub or scrape off when you are preparing the spears for consumption.

Control of Asparagus Beetles

Our asparagus patch is relatively small so I normally just hand pick the beetles and squish them when I find them. If you have a larger bed, this can become an overwhelming job. If you cut the spears when they are still pretty short (about 8″ or so), they normally don’t have much damage and early harvesting has the added benefit of removing any eggs before they have a chance to hatch.

Lady beetle adult

Lady beetle adult

Natural predators in your garden can reduce asparagus beetle eggs and the caterpillar-like larvae. A small parasitic wasp will attack and destroy the eggs. Lady beetles, which are similar in coloration to the spotted asparagus beetle but are round rather than oval in shape, will consume both eggs and larvae of the asparagus beetle. Another trick is to leave a few of the asparagus unharvested. Asparagus beetles are attracted to mature plants with a lot of foliage so these plants can become “trap” plants and the emerging spears are more likely to be left alone. In large plantings or when there are more severe infestations, pesticide applications may be warranted.

Bonide Neem Oil and Pyrethrin are good organic controls for asparagus beetles. These can be used pre-harvest or post-harvest according to the label directions.

For organic control post-harvest only, Bonide Captain Jack’s Deadbug Brew which contains spinosad is a good option.

Chemical insecticides to control asparagus beetles include Bonide Eight (permethrin) and Sevin (carbaryl). Be sure to apply according to the label instructions and ALWAYS follow the pre-harvest interval recommendations.

NEVER spray an insecticide (organic OR chemical) when the bees are active. Just because a pesticide is listed as organic doesn’t mean it isn’t toxic to bees and other pollinators. The best time to spray is in the early morning or in the evening when they are less likely to be collecting nectar. Once the foliage begins to yellow in the fall, cut the plants to the ground and throw the foliage in the trash rather than into the compost pile. Weed and rake up all plant debris around the asparagus bed. This will reduce overwintering sites and help lower populations of these beetles the following spring.

Until next time – Happy Gardening!

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View from the top of Reddish Knob

Last weekend Eric and I went on two amazing day trips to different places in the Allegheny Mountains of western Virginia. What a glorious weekend for hiking in the woods.

Huge bud of a hickory bursting open

Huge bud of a hickory bursting open

Up there spring was just starting. It was like traveling back in time about two weeks. In addition to taking in the beautiful views, we were hunting for spring wildflowers.

On Saturday, we drove to Hone Quarry in the George Washington National Forest. This recreation area sits at about 1,933′ and has several hiking trails running through it. We walked along one of the ridge trails for a while and saw lots of different budding and blooming wildflowers, as well as trees and shrubs that were beginning to break into growth.

Fringed Polygala or Gaywings (Polygala paucifolia)

Fringed Polygala or Gaywings
(Polygala paucifolia)

A white form of Gaywings

Less common white form of Gaywings

 

 

 

 

 

 

Sessile-leaved Bellwort (Uvularia sessilifolia)

Sessile-leaved Bellwort
(Uvularia sessilifolia)

Long-spurred Violet (Viola rostrata)

Long-spurred Violet (Viola rostrata)

 

 

 

 

 

 

 

 

 

Flower of Striped Maple (Acer pensylvanicum)

Flower of Striped Maple
(Acer pensylvanicum)

Dwarf Cinquefoil (Potentilla canadensis)

Dwarf Cinquefoil
(Potentilla canadensis)

 

 

 

 

 

 

 

Wintergreen (Gaultheria procumbens)

Wintergreen
(Gaultheria procumbens)

Partridgeberry (Mitchella repens)

Partridgeberry (Mitchella repens)

 

 

 

 

 

 

 

Hepatica flower

Hepatica flower

 

The name Hepatica comes from the foliage which resembles the lobes of the liver

The name Hepatica comes from
the foliage which resembles the
lobes of the liver.

 

 

 

 

 

 

 

 

On Sunday, we decided to drive up to the top of Reddish Knob, one of the highest points in Virginia at 4,397′ and the highest peak on the 73 mile long Shenandoah Mountain.

The drive to Reddish Knob was spectacular. We drove through an area where a fairly recent (within a few years) forest fire had gone through. The road appeared to be the firebreak and there was an interesting contrast in the vegetation between the two sides of the road.

Mountain Fetterbush (Pieris floribunda) was the predominant ground cover in the fire scorched woods. Many of the pines were killed.

Mountain Fetterbush (Pieris floribunda) was the predominant ground cover
in the fire scorched woods. Many of the pines were killed.

At one time, there was a fire tower on top of Reddish Knob – which is the primary reason that there is a road to the summit. From the parking lot, the site of the old fire tower, you feel like you are on top of the world with a 360° panoramic view of the surrounding area! Stunning!

On the way back down, we continued south on a rough dirt forestry road. It was great road but I’m glad we were in my 4-wheel drive truck! We made frequent stops to check out wildflowers and scenic views along the way.

Birdfoot Violet (Viola pedata) growing on a steep bank

Birdfoot Violet (Viola pedata)
growing on a steep bank

Wild Pink (Silene caroliniana) found a foothold in the rock face.

Wild Pink (Silene caroliniana) found
a foothold in the rock face.

 

 

 

 

 

 

 

 

Dwarf Iris (Iris verna)

Dwarf Iris (Iris verna)

A little sedum grows on a rock amongst lichen, moss, and a Christmas Fern

A little sedum grows on a rock amongst
lichen, moss, and Christmas Fern

 

 

 

 

 

 

 

 

Red Trillium (Trillium erectum)

Red Trillium (Trillium erectum)
grows beside a Striped Maple)

Wild Ginger (Asarum canadense) with its often unnoticed flower

Wild Ginger (Asarum canadense)
with its often unnoticed flower

 

 

 

 

 

 

 

 

Bloodroot (Sanguinaria canadensis) had gone to seed

Bloodroot (Sanguinaria canadensis)
had gone to seed

The curious flowers of Miterwort (Mitella diphylla)

The curious flowers of Miterwort
(Mitella diphylla)

 

 

 

 

 

 

 

Toothwort (Dentaria diphylla)

Toothwort (Dentaria diphylla)

Mountain Anemone (Anemone lancifolia)

Mountain Anemone
(Anemone lancifolia)

What an awesome way to spend a spring weekend!

Until next time – Happy Spring!

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