Posted on Categories Blog, Home, POP Orchards, VolunteersTags , , ,

POP will be celebrating partner/volunteer Eldredge ‘Rags’ Ragsdale with a Golden Persimmon Award at this year’s Orchard Dinner event on September 19th at The Woodlands. Rags is a true force of nature in his gardening efforts at multiple sites in North and Northwest Philadelphia, including POP partner sites Historic Strawberry Mansion and Awbury Arboretum.

The Community Garden at Awbury Arboretum Agricultural Village, established with the Pennsylvania State University Cooperative Extension in 1977, provides flowers, fruit, and vegetables to local residents and annually donates substantial quantities of food to emergency food services through the Pennsylvania Horticultural Society’s City Harvest program. Around seventy plots are lovingly tended to by many different gardeners with many more on the waiting list, and the whole garden is managed by a dedicated team that includes longtime member Eldredge Ragsdale, known by many in the Agricultural Village as “Rags.”

Eldridge ‘Rags’ Ragsdale is a long-time member and organizer at the extensive community garden at Awbury Arboretum’s Agricultural Village.

“They call me the President,” Rags tells me one May morning as he stands above a planting bed of tomatoes, kale, Swiss chard, and lettuce. “I started here working and helping other people out, next thing you know, they want you to be in charge and running the show!”

Originally from Virginia and presently retired, Mr. Ragsdale has been an active gardener at Awbury since purchasing a 10’x20′ plot in the garden for the 2007 growing season. Five years later he was elected President of the Board and has popularly overseen the Community Garden’s growth in the ensuing years. He spoke a little about the teamwork needed to ensure that everyone takes proper care of their plots, especially since there is a large group of new gardeners this year. This is in part so that the garden is in tip-top shape when the judges from the Pennsylvania Horticultural Society come to assess the space for the annual Gardening and Greening Contest, which the Awbury Arboretum Community Garden has previously won on several occasions. And it’s easy to see why, standing in the midst of all the garden’s greenery. According to other people I spoke to at the Agricultural Village, the sight of Rags working in the garden is a very regular one.

“I don’t count the time, I’ve just been rolling on through this thing,” he insists. “It’s almost like you retire off a job and then you get another job and you say, ‘dang, is this another job again?’ But it’s an easy job because […] you set your own course. I like this better; I’m outside all day, I can stop when I want to, I can sit down when I want to, and I can go to lunch when I want to— or I can go to lunch and don’t come back!”

This year, Rags is excited to complete a permanent gazebo in the center of the growing space to provide gardeners with better shelter from the weather. Currently, a temporary cloth structure stands in its place, but while it provides shade, rain tends to seep right through the roof. He is also looking forward to covering the cinder block edges of the raised beds with lids that will make it more accessible for senior citizens and gardeners with limited mobility to sit on the edge of their plot and garden comfortably. And, as always, there is the excitement that the fall harvest will bring. One of last year’s big achievements was planting a series of berry bushes near the fence around the perimeter of the garden, in addition to a number of fruit trees including apple and peach. “Hopefully they’ll show up this summer,” Rags tells me, “just bloom, bust out. Once I see that I’ll be like, ‘Wow! Look at what we accomplished this year.'”

‘Rags’ also volunteers as the lead caretaker of the orchard and gardens at POP Partner Historic Strawberry Mansion in East Fairmount Park, pictured here with their productive Trifoliate Orange trees!

In addition to the Awbury Arboretum Community Garden, Mr. Ragsdale has been working in the orchard and gardens at Historic Strawberry Mansion in East Fairmount Park for about the same time, or ten years. “I do the same work down there,” he explains. “I take care of the strawberries, I take care of the fruit trees, I take care of the blackberries, grapes — I love the grapes down there!” Historic Strawberry Mansion is a POP community partner, and the orchard and berry garden there was planted in 2013. Rags has been regularly involved with POP ever since, providing help with planting trees, pulling weeds, and pruning at both Strawberry Mansion and the neighboring Woodford Mansion. Coming together with other people to work with nature comes up regularly during our conversation. Rags says that that’s one of his favorite things about gardening, adding that “once [people] come in this gate, man, their personality is sort of more sober, subdued. It’s almost like in an oratory or a rectory or some place where it’s quiet all day and all you hear is birds, bees, and sometimes people conversing with each other… It’s like a cathedral.”

This POP Blog Post prepared by 2019 POP Intern Piotr Wojcik.  

SUPPORT US!  If you found this entry useful, informative, or inspiring, please consider a donation of any size to help POP in planting and supporting community orchards in Philadelphia: phillyorchards.org/donate.

POP TIPS: Black Knot on Cherry and Plum Trees

Posted on Categories Blog, Home, Orchard Care, Sprays, Tree Care, Tree DiseasesTags , , , , ,

Late-stage black knot infections on cherry (image from Cornell University)

Close up of late stage black knot infection on plum (image from Michigan State University)

Black Knot identification, symptoms, and life cycle

Sometimes, in the springtime, cherry and plum trees may develop subtle, velvety olive-green swellings on their branches or twigs. If left unattended, these swellings turn into large, brittle, unsightly black galls that can kill the whole limb or even stunt the growth of the entire tree. These galls are caused by an infection by the fungus Dibotryon morbosum or Apiosporina morbosa and are commonly called black knot disease.

The fungus overwinters in the knot and may take a few seasons to display visible symptoms, but it generally worsens from year to year. Galls vary in length between just an inch to nearly a foot and many times do not completely encircle the branch. Those a year old or older may become covered with the pinkish white mold of another fungus and may become riddled with insects, especially lesser peach borers. Trees with multiple infections become dwarfed and misshapen, markedly reducing their productivity and attractiveness. It’s extremely important to identify and remove any knots in the orchard to keep the disease from infecting other trees, since spores of the fungus are discharged from tiny sacs in the surface of the knots. Spores are spread by rain and wind to new growth, so discharge and infection are greatest during wet periods, at temperatures ranging from 55 to 75°F. A few greenish, corky swellings may become visible the fall after infection occurs, but most will not be noticed until the following spring. Often times, winter is the easiest time to inspect trees for infection since there are no leaves to hide any potential knots.

(Diagram from Dr. Wayne Wilcox, Cornell University)

Black Knot management

When getting rid of knots, prune off infected limbs 6 to 12 inches below the knot. Disinfect pruners between cuts with rubbing alcohol or a 10% bleach solution (1 part bleach to 9 parts water) and remember to deeply bury or remove the prunings from the site! If possible, remove any wild plum or cherry trees nearby. For persistent infections, apply two sprays of lime-sulfur, 7 days apart, before the buds begin to grow in spring. Spraying can help to limit the spread of this disease, but this must be combined with conscientious removal of galls as soon as they are identified.

Infection rates also depend on the particular cultivar of fruit tree. Orchardists looking to start growing plums and cherries should consider avoiding highly susceptible cultivars such as Shropshire and Stanley. Some recommended plum varieties include AU-Cherry, AU-Producer, AU-Rosa, AU-Rubrum, President, and Crimson. Meanwhile, tart cherry varieties such as Evans Cherry are reported to be less susceptible than other cherries.

Early stages of black knot infections result only in small galls, but remove them as soon as possible to protect your trees from further damage! (Cornell)

Make sure to check out POP’s plum and cherry scouting guides to be prepared for any other potential issues.

Additional resources

This POP Blog Post prepared by 2019 POP Intern Piotr Wojcik.  

SUPPORT US!  If you found this entry useful, informative, or inspiring, please consider a donation of any size to help POP in planting and supporting community orchards in Philadelphia: phillyorchards.org/donate.

Mason Bees: Philly’s Friendly Pollinators

Posted on Categories Beneficial Insects, Blog, HomeTags , , , , , , , ,
A blue orchard bee, Osmia lignaria, collecting nectar from a flower (Oregon State University)

You’ve probably heard the buzz about honeybees and how important they are to agriculture, but did you know that native bees such as mason bees are even better and more efficient pollinators of native crops? In fact, the species Osmia lignaria (pictured above) has been named the blue orchard bee for its recognized usefulness in pollinating fruit trees across North America. The blue orchard bee co-exists with the similar Japanese orchard bee Osmia cornifrons, which was introduced to the United States in the 90’s but is now well-established in the wild. Though more than 500 related species of bees exist in the Mid-Atlantic region, the blue orchard bee is one of the few native pollinators that is managed for agriculture in Pennsylvania.

Part of why mason bees are so prized for their pollinating power is that they emerge in early spring, when it’s still relatively cool and not many other pollinators are out. The life cycle of the blue orchard bee has evolved to coincide with the blossoming of fruit trees such as apricots, plums, pears, apples, and cherries- in fact they are generally only active for a few weeks around bloom time in March and April! Some other much-loved plants of this species include currants, gooseberries, elderberry, and huckleberry. Mason bees are special because they carry pollen on their abdomen instead of their legs, so when they land on individual flowers a lot of pollen is directly transferred from other blossoms. Another bonus as far as urban orchards are concerned, mason bees do not sting!

A female mason bee covering a nesting cavity with mud (David Biddinger, Penn State Extension)

Nesting patterns

Unlike honeybees, which are highly social and live in hives, mason bees are solitary, meaning that each female builds and takes care of her own nest (no queen here!). That being said, mason bees are often gregarious and will nest near other mason bees. Mason bees naturally nest in the hollow reeds of plant stems or in similar crevices that appear in their environment, such as cracks in firewood, slash removed from orchards, and cavities excavated by boring beetles in deadwood. After laying a single egg in each cell and provisioning it with a pea-sized mass of pollen for food, the female mason bee constructs a mud wall to close off the cell – just like a mason might build a house using mud bricks! Within a week, the eggs hatch, and the bee larvae spend the summer metamorphosizing into pupae and later onto adults, which then stay nice and cozy inside their home for the entire winter… until next spring, when it’s time to emerge and start the process all over again.

Mason bees tend to pollinate and nest not too far from where they emerge, so it’s relatively straightforward to introduce new populations to your orchard in the winter by purchasing tubes of cocoons containing adult bees from another local orchard that is already managing them. Keep the cocoons refrigerated at least until late March to prevent premature emergence during midwinter thaws, but release them no later than mid-May to reduce mortality. Purchasing new bees may be unnecessary, though, since wild mason bees in the area will be more than happy to accommodate artificial nesting material that you prepare for them.

This video demonstrates how to make one type of DIY mason bee nest (RescueDogTreats, YouTube)

Managing mason bees

Artificial nests can be made from wood blocks drilled with a series of holes, cardboard tubes with one end plugged, or sections of reed and bamboo with a stem node intact on one end. Ideally, each nest should have a 6 to 8-inch long internal tunnel that is about 5/16 of an inch in diameter. Mason bees generally lay female eggs first, since they will be the most insulated, with male bees on the outside, so if the tunnels are too shallow, you may not end up with enough females to do the hard work the following year!  These types of nests can be bundled together and placed horizontally throughout the orchard several feet above ground level under some sort of rainproof shelter. Some good locations include the sides of buildings, adjacent to cliff faces, or open sheds or garages, and a southward orientation encourages exposure to sunlight (but not too much). Remember to place your nests close to a steady source of mud! This can be as simple as an excavated hole with a dripping water hose or bucket.

Nests must be managed carefully in order to prevent the spread of parasites and diseases. Mason bee nests are often subject to predation by wasps, which can drill through wood to lay their own eggs on developing bees. Once the wasp eggs hatch, the larva eat the mason bee alive! One way to reduce wasp parasitism is to remove sealed nests from the orchard in the summer and move them to a dry, unheated and non-air-conditioned building such as a barn. Alternatively, the cocoons can be refrigerated for the winter.

Mites can also pose a serious problem to mason bee nests. Mite-infested cells are recognizable by the fluffy remains of shed mite skins and consumed pollen debris (rather than a compact ball of yellow pollen). Infested cells should be removed immediately to prevent further infestation, and healthy cocoons can be removed from the nests to be stored in refrigeration. Any nests intended for reuse the following year should be thoroughly cleaned and sanitized, or else the mason bees should be provided with new nesting materials in the spring.

Finally, as with many other beneficial insects, mason bees are very sensitive to pesticide use. Spraying should definitely be avoided during nesting season. Moving nests and nesting materials while the females are still constructing them can be very disorienting and will most likely result in abandonment of the nests.

Mason bees are often the first pollinators to come out in the spring (Seabrooke Leckie, Flickr)

Attracting solitary bees

In addition to providing valuable pollination services for fruit trees, blue orchard mason bees and other solitary bee species help diversify your orchard or food forest, leading to a healthier ecosystem, healthier humans, and a healthier planet. Providing them with nesting materials may attract wild bees in your area, or you could source them from another local orchard. Be on the lookout for these solitary insects in the early spring, and consider providing supplemental wildflowers to your garden, which will be appreciated by managed and native pollinators alike. Bees tend to be drawn the most to blue, purple, white, and yellow flowers.

Some specific native plants that bees love include…

  • Aster
  • Bee balm
  • Black willow
  • Blackberry
  • Blue wild indigo
  • Blueberry
  • Coneflower
  • Elderberry
  • Goldenrod
  • Trumpet vine
  • Lily
  • Lobelia
  • Maple
  • Milkweed
  • Phlox
  • Red buckeye
  • Rose
  • Sassafras
  • Serviceberry
  • Lupine
  • Violet
  • Turtlehead

Additional (re)sources:

Penn State Extension
Oregon State Extension
USDA Forest Service
Managing Alternative Pollinators: A Handbook for Beekeepers, Growers, and Conservationists
Phigblog: Making Mason Bee Homes

Where to purchase mason bees and supplies:

Pollinator Paradise
Back Yard Fruit Growers

This blog article written by 2019 POP Intern Piotr Wojcik.

SUPPORT US!  If you found this entry useful, informative, or inspiring, please consider a donation of any size to help POP in planting and supporting community orchards in Philadelphia: phillyorchards.org/donate.