What is eating the Cannas?

On August 28, 2017August 28, 2017 By durhammastergardenersIn Gardening information

By Jane Malec, EMGV

While volunteering at the Bahama Farmer’s market, an interesting discussion developed on the plight of the once beautiful stand of cannas near the roadside. The leaves looked curled and ratty…so sad.

Cannas are one of the plants we depend on during the warm summer months. With its colorful leaves and huge iris like flowers, they’re a bright spot in the garden. As tropical plant, they will stand up to the heat plus they are not at the top of the deer menu! Also, these rhizomes are generally easy to grow.
Although they are largely free of pests, there are two that you need to look out for. Canna leaf rollers can be a real problem and is what we uncovered in the large bed at the farmer’s market. Stalk borers can also cause big headaches.
The leaf rollers, also known as Brazilian skippers, chew straight rows of holes on canna leaves. Some rollers feed in groups under a netting of their own silk. The solitary types feed by rolling, folding or tying leaves together before they eat them. This last process is actually very interesting as it looks like the leaves have been sewn with a needle and thread. Leaf rollers are active at night while sleeping on the underside of the leaves during the day. The damage to young leaves usually prevents them from opening and they may die. Infested plants can’t bloom and are ugly. Its easy to miss the first generation of these caterpillars if you aren’t monitoring the rolled leaves carefully. The second and third generations will be more obvious because by then the damage will be extensive.

If you are able to detect these vile caterpillars early enough, you can cut the leaves and destroy them or wash them off. Unfortunately, washing them maybe unproductive if there are many leaves as we found in Bahama. You can also use a systemic insecticide such as a 3-in-1 for roses. There are other options including insecticidal soap. Bacillius thuringienis is also effective if applied to the sticky underside of the leaves. Even a household detergent may work if applied to the leaf underside.

Stalk borers have a broad host range upwards of over 200 species of plants. This little villain can go after cannas, tomatoes, goldenrod and even some fruits. Sometimes even twigs of some trees are victims. The first sign that you have stalk borers in your canna will be wilting leaves but by this time, its often too late. You can try to kill the borer by cutting into the infected stem and digging it out. Your best bet is to remove the infested plant and then kill the borer. This problem is often sporadic and thereby difficult to predict which plant will succumb. Please check the second link at the bottom for greater detail on this pest.

Here comes some very important advice for both of these insect problems…discard all of the plant material after die back no matter when that is! DO NOT COMPOST! The leaf roller and stalk borer larva will overwinter in dead leaves. If you have a big stand of cannas and don’t clean up the debris throughly it will most likely present an even bigger problem next season.

There will also be the occasional slugs, snails, thrips and mites to deal with and should be treated as you do with another plants.

My cannas are in a pot and are three years old. So far I have not experienced either of these little menaces but I am inspecting the leaves very closely now.

http://www.aces.edu/pubs/docs/A/ANR-1315/ANR-1315.pdf

https://www.extension.umn.edu/garden/insects/find/stalk-borers/

Entire State Under Quarantine for Emerald Ash Borer

On September 16, 2015 By durhammastergardenersIn Gardening information

FOR IMMEDIATE RELEASE
THURSDAY, SEPT. 10, 2015

CONTACT:

Phillip Wilson, plant pest administrator
NCDA&CS Plant Industry Division
919-707-3753

Entire state now under quarantine for emerald ash borer

RALEIGH – Agriculture Commissioner Steve Troxler signed an emergency order today expanding the quarantine for emerald ash borer to include the entire state, following the discovery of borers in several more counties across the state.

“We have surveyed the state to see if we could find evidence of this highly destructive pest in previously undetected counties,” said Agriculture Commissioner Steve Troxler. “Our staff have now turned up evidence of emerald ash borers in the central, eastern and western parts of the state, including areas near the borders with Virginia, Tennessee and South Carolina.”

The quarantine allows for the in-state movement of hardwood firewood and plants and plant parts of the ash tree, including living, dead, cut or fallen, green lumber, stumps, roots, branches and composted and uncomposted chips. However, movement of these items outside the state into non-quarantined areas would be prohibited. Firewood that has been treated, certified and labeled in accordance with federal regulations can be moved outside the quarantine area.

North Carolina becomes the 15th state in the country with a statewide quarantine. The beetle was first detected in the United States in Michigan in 2002. It is responsible for the death or decline of tens of millions of ash trees across the country.

“This is a devastating pest to ash trees, eventually killing the trees where the insects are found,” Troxler said. “We are not surprised to find more infestations in the state, particularly along the borders with Tennessee and Virginia, two states where borers have previously been found. Virginia also has a statewide quarantine in effect, and Tennessee has quarantines in nearly half of its 95 counties.”

The Plant Industry Division and the N.C. Forest Service are working in cooperation with the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service. Contact the USDA State Plant Health Director for more information on federal quarantine regulations and firewood certification at 919-855-7600.

Symptoms of emerald ash borer in ash trees include a general decline in the appearance of the tree, such as thinning from the top down and loss of leaves. Clumps of shoots, also known as epicormic sprouts, emerging from the trunk of the tree and increased woodpecker activity are other symptoms. The emerald ash borer is not the only pest that can cause these.

Emerald ash borers overwinter as larvae. The adult beetle is one-fourth to a half-inch long and is slender and metallic green. When the adults emerge from a tree, they leave behind a D-shaped exit hole. The larvae can also create serpentine tunneling marks, known as feeding galleries, which are found under the bark of the infested trees.

Home and landowners are encouraged to report any symptomatic activity in ash trees to the NCDA&CS Plant Industry Division hotline at 1-800-206-9333 or by email at newpest@ncagr.gov, or by contacting their local N.C. Forest Service County Ranger. To find your county ranger, go to http://ncforestservice.gov/contacts/contacts_main.htm. Rangers can also suggest treatment options for homeowners.

The pest can affect any of the four types of ash trees grown in the state.

Franklin and Wake counties join quarantine area for emerald ash borer

On June 30, 2015 By durhammastergardenersIn Gardening information

FOR IMMEDIATE RELEASE
TUESDAY, JUNE 30, 2015

CONTACT: Phillip Wilson, plant pest administrator
NCDA&CS Plant Industry Division
919-707-3753

RALEIGH – Franklin and Wake counties are the latest to come under quarantine rules restricting the movement of hardwood firewood, ash nursery stock and other ash materials after emerald ash borers were confirmed in both counties. Agriculture Commissioner Steve Troxler signed an emergency quarantine order allowing the expansion.

An emerald ash borer was found via the capture of a cerceris wasp in Franklin County. The N.C. Department of Agriculture and Consumer Services’ Plant Industry Division had been monitoring sites in Franklin County and throughout the state looking for evidence of EAB. Part of the monitoring included capturing cerceris wasps around baseball fields to see what food sources or insects they were bringing back to their underground nests. The method had been used to find EAB in Connecticut, and North Carolina is only the second state to successfully use this method in the United States.

Evidence of EAB was found by NCDA&CS staff in woods near the Raleigh-Durham International Airport.
“This brings the total counties in the state under EAB quarantine rules to seven, with detections in Granville, Person, Vance and Warren counties in 2013 and Wayne County earlier this year,” Troxler said. “We continue to monitor other counties for this highly destructive pest by trapping areas with ash trees. If you see the purple, triangle-shaped traps, please do not disturb them.”

The beetle was first detected in the United States in Michigan in 2002. It is responsible for the death or decline of tens of millions of ash trees across the country.

Under the state quarantine, all hardwood firewood and plants and plant parts of the ash tree — including living, dead, cut or fallen, green lumber, stumps, roots, branches and composted and uncomposted chips — cannot be moved outside the county.
The Plant Industry Division and the N.C. Forest Service are working in cooperation with the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service.

Symptoms of emerald ash borer in ash trees include a general decline in the appearance of the tree, such as thinning from the top down and loss of leaves. Clumps of shoots, also known as epicormic sprouts, emerging from the trunk of the tree and increased woodpecker activity are other symptoms. The emerald ash borer is not the only pest that can cause these.
Emerald ash borers overwinter as larvae. The adult beetle is one-fourth to a half-inch long and is slender and metallic green. When the adults emerge from a tree, they leave behind a D-shaped exit hole. The larvae can also create serpentine tunneling marks, known as feeding galleries, which are found under the bark of the infested trees.
Home and landowners are encouraged to report any symptomatic activity in ash trees to the NCDA&CS Plant Industry Division hotline at 1-800-206-9333 or by email at newpest@ncagr.gov. The pest can affect any of the four types of ash trees grown in the state.

What’s That Bug? Leaf Footed Bugs in the Garden

On June 25, 2015June 24, 2015 By durhammastergardenersIn Gardening information

I work in a garden with a group of volunteers. The other day, a sharp eyed person pointed out some bright orange-red bugs like these on the leaves of one of our potato plants.

These are the nymphs of the leaf footed bug, a relative of stink bugs. Adult leaf footed bugs are brown, with a flattened, leaf-shaped area on their hind legs. Both the nymphs and adults are pests that damage buds, flowers, fruits and seeds. Leaf footed bugs feed on many plants, including tomatoes, peaches, blueberries, beans, okra, and pecans. When these bugs feed on tomato fruit, they cause yellow, hardened spots to develop. Feeding on other fruits can cause brown spots to shriveled, misshapen fruits, depending on the number of bugs and the time the fruits are damaged.

Adult leaf footed bugs overwinter in weedy areas or under mulch and debris. They lay eggs in a row on the undersides of leaves or on stems. Eggs hatch in 5-7 days, and nymphs mature in 25-30 days.

Leaf footed bug adult Photo: Debbie Roos, NC Cooperative Extension — Leaf footed bug adult
Photo: Debbie Roos, NC Cooperative Extension

Leaf footed bugs and their stinkbug relatives are difficult to control, but scouting for these pests now will help keep populations from building up throughout the season. Removing the nymphs and adults by hand and dropping them into a container of soapy water is an effective means of control when populations are small. You may want to wear gloves when picking leaf footed bugs from your plants – they do have an unpleasant smell. There are few organic pesticides that are effective on these bugs, but hand picking now and reducing places where the adults can overwinter will help keep next year’s population in check. If you choose to use an insecticide to control a large population of leaf footed bugs, pyrethroids can be used as directed.

Just a quick word of caution, though – some assassin bugs (beneficial insects) are also orange and can look similar to the leaf footed bug nymphs shown above. For photos of assassin bugs, click here

For more information about leaf footed bugs:

http://pender.ces.ncsu.edu/2011/07/staying-ahead-of-stink-bugs/

http://www.ent.uga.edu/veg/solanaceous/leaffootedbuts.htm

http://growingsmallfarms.ces.ncsu.edu/growingsmallfarms-leaffootbug/

Insect Pest Alert – Granulated Ambrosia Beetles

On June 1, 2015May 31, 2015 By durhammastergardenersIn Gardening information

In recent weeks, the Extension office has received several calls about trees being damaged or killed by Ambrosia Beetles. This beetle was introduced from Asia in the 1970s and attacks a variety of deciduous trees and some shrubs. Although they attack healthy trees, trees that are stressed in any way are at greater risk. Female beetles bore into wood and excavate galleries for their young. Beetles also inoculate the trees with fungus, from which the adults and young feed.

According to Michelle Wallace, Durham Co. Extension Agent,

“Some of the characteristic symptoms of an Ambrosia Beetle Infestation include:

1)      Tiny holes in the bark of the tree
2)      Sawdust that looks like little toothpicks sticking out of the tree
3)      Dieback of the upper branches of the tree

Once the infestation occurs death always follows – there is no cure.

However, action must be taken to remove and destroy the infested wood. This insect has many hosts and is particularly attracted to trees under stress – though can and will attack healthy trees as well.”

Sawdust plugs pushed from a tunnel. Photo: C. S. Gorsuch

Adult Granulated Ambrosia Beetle (formerly Asian Ambrosia Beetle). Photo: NSCU.edu

Control of this pest is difficult. Infested plants should be removed and destroyed. Monitor trees for signs of pests, and avoid conditions that will cause stress. For more information, please see the following links:

http://www.ces.ncsu.edu/depts/ent/notes/O&T/trees/note111/note111.html

http://www.clemson.edu/cafls/departments/esps/factsheets/turforn/ambrosia_beetles_to22.html

http://entnemdept.ufl.edu/creatures/trees/asian_ambrosia_beetle.htm