November News

---

  The spotted lanternfly, Lycorma delicatula, is an invasive species that has been wreaking havoc  in the eastern United States since 2014. It has expanded its range significantly this year, making headlines as a nuisance in New York City, appearing in two locations near Cleveland, Ohio, and, most recently, being discovered in the insect collection exhibited by a 4-H club member at the Kansas State Fair. The insect was reportedly discovered dead earlier this summer on the family’s patio in northwestern Kansas, far from any other known infestation.

   The spotted lanternfly feeds on a variety of crops, including grapes, apples, hops, walnuts and hardwood trees. The waste it excretes encourages a fungal growth called sooty mold, which can kill plants by blocking sunlight from reaching their leaves.  Experts fear the continued spread of spotted lanternflies could severely hurt the country’s grape, orchard, and logging industries. Beekeepers have also reported that bees, feeding on the sugary excrement of this leafhopper, return to their hives with the sooty mold spores which then contaminate the honey.

   Since arriving in Pennsylvania in 2014, presumably in a shipping container from Asia, the spotted lanternfly has spread and populations are currently found in 11 states including: Connecticut, Delaware, Indiana, Maryland, Massachusetts, New Jersey, New York, Ohio, Pennsylvania, Virginia, and West Virginia..  The insect is a poor flier and moves much like the gypsy moth, laying masses of eggs on various surfaces that are then moved by humans. Lanternflies are particularly fond of Ailanthus, also known as tree of heaven, an invasive species which is frequently found along roadsides and rail lines. The two populations near Cleveland, Ohio were found near railroad tracks and separated by a short distance.

   While the presence of one specimen doesn’t mean there’s an infestation, officials with the USDA and the Kansas Department of Agriculture plan to keep surveying Thomas County for more spotted lanternflies.  All state agricultural agencies are encouraging the public to be especially alert at this time of year when the insects tend to gather in large groups.  Now through November is the best time to spot the SLF because it is in its most recognizable stages as a colorful winged adult plant hopper. After hatching in the late spring, the SLF goes through four nymph stages. By midsummer, the nymph SLF can be identified by its red body, roughly a half-inch in size, with black stripes and white dots. During the late summer until roughly November, the SLF is in the adult stage. These adults are larger, roughly one inch in size, with black bodies and brightly colored wings. When preparing for the winter holidays, check outdoor items for spotted lanternfly egg masses, including those items you may bring indoors. Scrape any egg masses into a plastic zippered bag filled with hand sanitizer, then zip the bag shut and contact your local Extension office. Inspect your trees and plants for signs of this pest, particularly at dusk and at night when the insects tend to gather in large groups on the trunks or stems of plants. Inspect trees (in particular, tree of heaven), bricks, stone, and other smooth surfaces for egg masses.

   Those who grow black walnuts, pecans, and chestnuts have their eyes glued to weather radar, hoping for a few dry, breezy days to facilitate crop pollination. Although the allergy counts have included figures for black walnuts, the weather hasn’t been prime for pollination. In the case of black walnuts, pecans, and chestnuts, a warm, gentle breeze is exactly what the grower ordered. 

   Black walnut produces both male (pollen-producing) catkins and female embryos on the same tree. While most trees are probably self-fertile, having a second tree around is always considered an asset. The same is true of pecans, where some trees have female structures that will produce nuts, on the same tree as pollen (male) producing catkins. Pecans may be either female or male dominant…not the scientific multi-syllabic term…some have female flowers that are ready for pollen before the male flowers on that tree shed their golden dust. On others, the pollen production precedes the receptibility of the female (nut-producing) structure. Unless you are in a pecan desert, there is probably enough pollen to fertilize your trees…unless rain continually cleanses the air!

   Growers have their eyes glued to the skies, and to their twigs, hoping for a successful pollination season.

   Groundhog Day may occur in February but it is a reminder that Spring is on the way and that there is work to be done in the nut orchard before warmer weather arrives. Those intent on improving production are busy collecting scion wood from trees known to have the characteristics that will help them reach that goal. These “winners” may produce more nuts, larger nuts, or be disease-resistant.

   In young orchards, existing trees that have exhibited vigorous growth the previous year are candidates for the conversion to improved stock. There are many different styles of grafts and becoming familiar with several provides you with options appropriate for different situations. The scions, however, all share similar characteristics: they come from growth made in the previous year and have at least two inches of stem separating the buds. This spacing allows you to trim the stem to expose the cambium, the growing layer of cells that lay below the bark and will merge with the cambium exposed on the root stock. Scion material should be at least pencil diameter; anything larger than 3/8 inch diameter is generally difficult to trim.

   Veteran grafters advise that the most successful grafts come when scion material is collected after three days when night temperatures have been above freezing and day temperatures have been in the 50s. Using a bypass pruner, cut the scion material from the donor tree and then cut into lengths that will fit into your plastic bag. If using small bags, make certain that there are at least 3 buds on each scion. Label the bag with the identity of the donor plant, add a slightly moistened paper towel, and refrigerate. Don’t allow the scions to freeze and don’t store in a refrigerator that contains apples as the ethylene gas they give off will kill the scion. Check the bags weekly to be sure that mold hasn’t developed.  

   February also provides an opportunity to jump start a new nut orchard from existing, larger trees. Coppicing a tree, cutting it back to ground level, stimulates the production of new shoots during the growing season. The technique is most effective on trees up to 5-6 inches in diameter and the resulting sprouts will be ready for grafting in the following year. The energy stored in the root system supercharges these sprouts. If you cut one or two trees and leave knee-high stumps, you can make several bark grafts around the top and produce an abundance of scion material to cut the following year as well.

   The Missouri Nut Growers Association schedules an annual grafting workshop that is open to all and provides a hands-on opportunity to learn this valuable skill. The arrival of COVID-19 forced cancellation of the 2020 gathering but we are hopeful that we will be able to offer this opportunity in 2021. We’ll announce our plans on this website in mid-April. The Center for Agroforesty has an excellent publication that illustrates several grafting techniques which is available at: https://extension2.missouri.edu/media/wysiwyg/Extensiondata/Pub/pdf/agguides/agroforestry/af1003.pdf. 

   Nuts and Christmas…it’s a natural pairing. Whether roasting chestnuts over an open fire, snacking on a can of assorted salted kernels, cracking pecans and walnuts collected from a tree in the backyard, or baking nut-rich cookies…’tis the season. Cans of vacuum-packed nuts are usually relegated to the snack aisle, you’ll find small packages of nuts destined for baked goods featured with the bags of flour and sugar, and the November/December holiday season finds them, in shell, piled with the produce. The harvest is complete for most Missouri-grown nuts, although a few pecans may remain on the ground awaiting a spell of dry weather so that they can be swept up by machinery. With COVID quarantines as well as suggested restrictions on travel and gatherings, marshalling family fingers to crack shells and pick out nutmeats for future use can make good use of otherwise empty hours. However, if you’re going to invest time and effort in this project, go the extra step and properly store your finished product.

   Pecans and black walnuts ripen late in the year so processing them in the colder months makes good sense: the time from tree to table is minimal and who can argue with the smells of freshly baked cookies or the additional heat from the stove. To properly save the bounty that remains, nuts should be frozen, either in the shell or as cleaned meats. Nuts in the snack aisle usually maintain their quality: they don’t spend as much time on the shelf and they are vacuum packed. No history comes with store-bought nuts in the baking aisle and they may have spent considerable time sitting on pallets in a warehouse before reaching the store shelf and your pantry. Although COVID confinements have provided more time for home cooking, the price of a small package of kernels can be a deterrent. The oils turn rancid when nuts aren’t stored properly, imparting an off taste that is easy to detect. The “bold, robust taste” attributed to black walnuts often indicates that they haven’t received the TLC that guarantees high quality in the end product. Find a local grower who has improved cultivars and you’ll have a thinner-shelled, meatier black walnut to crack for your cookies.

   The Chinese chestnut is becoming increasingly popular to the holiday scene and adds a fourth face to the nut family. Unlike pecans, hickories, and black walnuts, chestnuts do not contain oils and must be stored in the cold and humidity of the refrigerator produce drawer. Unfortunately, most grocery stores selling fresh chestnuts offer them in open bins next to the “oily” nuts and the end result is moldy kernels or dried kernels that rattle inside the shell. Once the fresh chestnuts have been roasted and shelled, they can be frozen for future use. Like pecans and black walnuts, purchasing directly from a grower is the best way to get a quality product. If you haven’t already acquired your chestnuts for this holiday season, you may be out of luck when it comes to ordering directly from a grower or consolidator: demand is high and most of the crop is sold before the end of November. 

   Don’t forget to leave Santa a generous helping of nuts on Christmas eve. Be they a salted snack or incorporated into a plate of cookies, you won’t find leftovers in the morning!  

  Chestnuts have been celebrated in song and verse, but the chestnuts of today don’t match the lore of the past. Rather than waiting for frosty days, the Chinese chestnut now planted in Missouri is harvested from mid-September through the following weeks, typically ending by early November. The village smithy would have been dodging large, prickly burs and quarter-sized (or larger) nuts. The American chestnut was a prodigious mast producer but those nuts were considerably smaller than The Chinese and Japanese nuts enjoyed by Asian and European cultures who now seek them in the United States.

   The fist-sized burs of Chinese chestnut may contain three nuts, although it’s common for one or two of them not to develop. As the nuts ripen, the burs split open on the tree and the nuts fall to the ground. The burs drop as well, sometimes before they’ve fully opened and the nuts are still inside. Dry, warm, sunny days trigger the fall and a stiff wind can trigger a massive, continual drop throughout the day. 

   While mechanical harvesters exist, they are expensive. Some individuals will rely on large vacuums to gather the nuts while others will hire hand labor. A flexible back and a sturdy pair of leather gloves are basic equipment as well as separate buckets for burs and nuts.

   Chestnuts grow quickly and frequently produce their first crop before they are 10 years old. That crop increases each year and, unless there is a problem during the pollination period or a late frost, it is quite reliable. Once they are too large to be browsed or rubbed by deer, the trees have few issues. Dealing with the nuts, however, is a different story. Daily collection is required if you don’t want the local deer, squirrels, and other rodents to commandeer your harvest. Once you’ve handled burs, you’ll have grudging admiration for the squirrels that go so far as to cut and carry the burs from the tree. Occasionally a pet dog will take an interest in chestnuts…first as a toy and then as a food item.

   The most serious issue with chestnuts comes from weevils that infest the nuts. Again, one must have grudging admiration for an insect that can maneuver around the spines and lay eggs in the developing nuts. The weevil grubs, like those of hickory nuts, develop in the kernel and then emerge from the nut and enter the ground to pupate, emerging the following spring. Spraying is one control technique but the spring emergence finds them headed for the blooms, along with a host of other pollinators. The grubs are killed by extended temperatures above 117 degree and growers use hot water baths to kill the small eggs and larvae. Sanitation is critical in the chestnut orchard and removing all nuts and burning the burs is another technique to control weevil populations. Unfortunately, the nuts that squirrels bury serve as the source of future weevils. Many of these sprout so that once you have one chestnut tree you’re going to many chestnut trees.

   Chestnuts are referred to as the “un-nut”, as they have no oils and become dry and hard if stored outside of the refrigerator vegetable drawer. That has made it difficult for new consumers to appreciate its rich flavor which is brought out by roasting or other heating. Scoring the shell of a dozen nuts with a sharp knife or box cutter and microwaving for 2 minutes cooks the nut and makes it easy to remove the shell and brown, papery coating on the nut (pellicle).

   The MU Horticulture and Agroforestry Research Center will conduct its annual Chestnut Roast as a virtual event in 2020. They will release a set of novel videos on specialty crop production (pecan, Chinese chestnut, and elderberry), maple syrup production, and other topics.  Presentations will be available at 8:30 a.m. on Saturday, Oct. 3, on the new Mizzou Agroforestry YouTube channel.  Those who “subscribe” to the channel now will receive notifications as new content becomes available. The Chestnut Roast videos will also be linked through the Horticulture and Agroforestry Research Center Facebook page, the Center for Agroforestry Facebook page, and the HARC website. 

   Can any school child find the Suwanee River on a map? If they’ve heard the song, do they have any idea of where they might find a pawpaw patch way “down yonder”?

    Although few are actually familiar with the largest native fruit in North America, plenty of folks have claimed it as it is also known as the Hossier banana, the Missouri banana, the Michigan banana, and the West Virginia banana. Thanks to the efforts of a persistent group of school children, the pawpaw became the official state tree of Missouri in 2019.

   Pawpaws ripen in late August and through mid-September.  The green fruit gradually become more yellowish and soft under thumb pressure. Native Americans and early explorers relished the fruits once they turned black and had a butterscotch taste. Like overripe bananas, they were certainly edible but most modern taste buds and eyeballs prefer the freshly ripe fruit. The trees are frequently found in groves as they often propagate by forming new plants from root shoots. Unfortunately, fruit is seldom found in the most luxuriant patches of pawpaws. Because the tree can produce numerous shoots from its roots, these stems are all identical and, in order for fruit to form, the flowers must receive pollen from a genetically different pawpaw flower.  Of course, there is competition from wildlife if you go seeking pawpaws. The flesh, which tastes like a mix of banana and pineapple, appeals to critters like raccoon and opossum and, in many situations, the seeds they consume would pass through their digestive tract and be sown at a different location. Because the large seeds in the fruit won’t germinate if they dry out, unless they somehow end up in a favorable setting, a new pawpaw patch cannot form.

   Fewer and fewer young folks are going afield, splashing in creeks, building forts, in the woods, picking berries, and generally reveling in the outdoors so they seldom look for, know of, or discover pawpaws. With a bit of effort, the tree can become part of an “edible landscape” in your yard.  Although characterized as a bottomland, understory tree, they perform well in most mesic settings. You can purchase potted or bare root stock from specialty nurseries: the potted trees will be far easier to plant. Young trees do best in partial shade, which can be provided with commercially available shade cloth or a discarded pair of sheer curtains. If you are fortunate enough to find pawpaw fruit, you can plant the seeds in the fall. Be forewarned that the seeds are slow to germinate, in some cases not sending up a shoot for two or three years. You’ll need two trees (if grafted, they must be the different cultivars) to produce fruit. It’s not unusual for the tree to die back to the ground and then resprout from the root, sometimes for several successive years, as it becomes established. 

   Once established, the pawpaw requires minimal care. If you have an established white-tailed deer population, protect the tree from rubbing in the fall and winter with a sturdy wire cage. Pawpaws are extremely sensitive to herbicides and some of the commonly used fruit tree sprays. The leaves are fodder for zebra swallowtail butterfly caterpillars but it is the Asimina webworm that is responsible for most concern, especially on young trees where it can reduce all the leaves to masses of brittle, dried foliage. Frequent dusting with BT dust can help to control this pest. There is also a pawpaw sphinx moth, the mature form of a hornworm caterpillar (similar to that frequently encountered on tomatoes) which feeds on pawpaw leaves. 

   The taste of pawpaw fruits can vary from tree to tree and some individuals detect an undesirable aftertaste. Pawpaws can be eaten fresh or the pulp, separated from the seeds and skin, can be used to replace banana in banana nut bread, baked in a custard pie, or frozen as an ice cream. The seeds and skin should not be consumed!

   If you’re out an about in the woods this month, watch for the large, single, dark green leaves that smell like green pepper when crushed. You just found your pawpaw patch!

   It’s July…it’s summertime! Growers are out inspecting their trees to get an idea of the crop they will harvest later this year. This may be easy, as in the case of elderberries, where the white panicles of blooms are borne at the tips of stems and the green berries, ripening to purple are near eye level. Pawpaw fruits are large enough to be seen, even though tucked among the enormous green leaves. Persimmons are also visible, although require a keen eye as they are nearly the same shade of green as their surrounding leaves. Walnuts and pecans are readily visible at the tips of branches…if pollination was successful. Even during years with adequate pollination, trees may not produce a large crop if they made a lot of nuts the prior year. This on-again, off-again phenomenon, known as alternate bearing, is often triggered by boom crops, which drain energy from the tree as they ripen in the fall, leaving minimal energy to form female flowers for the next year. Chestnut burs are still tiny, but will grow quickly over the summer, maturing mid-September thru mid-October.

   Spring pollination is only one hurdle faced in the marathon to produce a fall harvest. Summer thunderstorms with high winds and hail, can damage leaves, break branches, and even snap and uproot trees that have all that additional crop weight “upstairs”. It’s said that Missouri is only 10 days away from a drought as heat and plant needs pull the moisture from the soil and it is the water that is available at this time of year that is critical for nut sizing and the beginning of kernel fill. 

   Exploring details of water needed by pecan trees, known for their bottomland habitat, led me to the Noble Research Institute in Ardmore, Oklahoma. About 350 researchers from a range of disciplines and from 20-plus countries work at the Institute headquarters in Ardmore, Oklahoma, and on research farms in the surrounding area, to carry out the vision of Lloyd Noble.  Lloyd Noble established the Noble Research Institute (originally named The Samuel Roberts Noble Foundation) in 1945 to help revitalize agriculture after the Dust Bowl. Today, the Noble Research Institute is the largest nonprofit agricultural research organization in the U.S.  A paper written in 2006 summarized pecan water needs and I’ve summarized its contents in the following paragraphs. To read the full paper, visit: https://www.noble.org/news/publications/ag-news-and-views/2006/september/consider-pecan-trees-water-needs-during-drought/. 

   Many people have asked how much water a pecan tree requires and estimates have ranged from as low as 30 inches per year to as high as 72 inches per year. Of course, there are a number of other variables to consider, such as soil type and the physical location of the tree as well as timing, with moisture most critical during the growing season. Trees in a flood plain have a much different regime than those planted in sandy, rocky soil.  A tree growing in a soil that is seven feet deep has the potential of 9000 gallons of available water per tree compared with a 7 inch deep soil, which has the potential of only 800 gallons of water per tree. Pecan tree roots range far beyond the canopy, as can be seen if you’re present during a tree shaking during the fall nut harvest. The folks at Noble figured that, on the basis of 55 inches of precipitation per year, with most arriving during the growing season, individual trees in a planting with 35 trees per acre, would need 190 gallons of water per day. By comparison, the standard recommendation for water requirements of pecan trees is 1 to 2 inches per week. At the same spacing, this amounts to 111 gallons per tree per day.

   Here in St. Clair County, Missouri, the 2019  walnut crop on the farm was a good one, and harvested by energetic squirrels as other nuts were in short supply. This year a few trees have nuts so I will make my harvest in early July and intend to convert the nuts I can reach into Nocino, an Italian liqueur. If you’re interested and can find a few green black walnuts that haven’t yet hardened the shell inside the hull, here’s a link to a recipe I Googled: https://www.mountainfeed.com/blogs/learn/45965569-how-to-make-nocino-an-italian-walnut-liqueur. Perhaps it will prevent COVID-19 infections. For certain, overindulgence will mean that you won’t care!

     Across Missouri, grafting knives are being sharpened and scion storage refrigerators are being opened as nut growers head to their orchards to graft material taken from high quality trees earlier this year to rootstocks of run of the mill trees.

     Grafting has been practiced for thousands of years although its actual origin is up for discussion. The first definitive written account is attributed to writings from Greece dated 324 BCE but the descriptions detail a number of practices that were apparently commonplace. Grafting not only allows you to faithfully replicate a high quality tree but is also used to combine characteristics of the rootstock, such as dwarfing and disease resistance, with the high quality fruit produced by the scion.

     There are a number of different grafting techniques which can be used. All focus on matching the cambium, a thin layer of growing cells just below the bark, of the scion and rootstock. Grafts can be used on everything from very small saplings to large trees, where bridge grafts are employed to save damaged trees, for example, where beaver have effectively freshly girdled a tree, disrupting the flow of nutrients up and down the trunk, but the tree hasn’t been damaged to the point that it will drop. About the only caveat is that the scion and rootstock must be the same or closely related species.

     Many grafting techniques are demonstrated on U-tube videos, but not all provide good results when used on nut trees. The publication” Propagating Pecan and Black Walnut (available to download at: http://extension.missouri.edu/explorepdf/agguides/agroforestry/af1003.pdf) is a good introduction to those specifically recommended for nut trees. Another, more general but also helpful, grafting reference is the MU Extension publication titled “Grafting” (https://extension2.missouri.edu/g6971). The side graft, in Figure #4, is simple and also effective and can be accomplished using a pair of bypass pruners and a utility knife. The trimmed scion is inserted into a cut made into the side of the rootstock that is opened by pushing on the portion of the stem above the opening. When that pressure is released, the stem springs back, holding the scion in place. Of course, you must wrap the junction with grafting tape to reduce moisture loss from the cut edges. By cutting the rootstock about four buds above graft, you build in a bird perch without attaching a separate stick.  Little details: the FLAT slope cut on each side of the scion should leave equal amounts of material on both edges, otherwise only one exposed cambium will contact the cambium of the rootstock.  If the scion isn’t large enough to entirely bridge the width of the cut, all is not lost. You can trim another stick or simply match one side as this is often successful. 

     Followup care of the graft consists of monitoring rootstock buds above the graft and rubbing them off at the first sign of greening: if you don’t check carefully, that vegetation may lead you to think your graft has been successful when it has failed. Once the graft has begun to green, attach a second, taller stick to the rootstock to keep birds from landing on the tender sprouts.

     The grafting techniques discussed here are best done in the spring, when the nut trees are breaking dormancy and before temperatures become excessive as grafts often fail once temperatures get above 90 degrees. Not all grafts will be successful but making certain that the scion material has been stored properly and is still dormant, careful alignment of the cambial layers of the scion and rootstock, and protecting the graft union from desiccation will greatly improve the likelihood of success. While the text and pictures referenced here will be helpful, nothing beats seeing the process in action and hearing the tips of an experienced grafter. The Missouri Nut Growers Association offers such an experience at its annual grafting and scion exchange meeting. Unfortunately, due to COVID-19 it was necessary to cancel the event this year. The 2021 event should take place in late April or early May, so revisit out home page after April 15, 2021, for an update.

   Scion exchange update...In light of the spring grafting meeting being canceled, I'll be facilitating an informal scion exchange. Several folks have offered up scion and there have been several request for scion - all of which is GREAT! The the following scion is available. Pecan - Kanza, Pawnee, Gardner, Shepherd, Yates 68, Lakota, Major, Meramec, Harc, Chetopa and Manson 1.

Black Walnut - Kwik Krop, Football, Hay, Emma Kay, Neel and Tom Boy

And some English Walnut.

Please feel free to contact me. I can be reached at 816-293-5819 (leave a message) or via email mjlucas861@gmail.com. 

I plan to do/coordinate the shipping the week of April 13.

Thanks, Mike Lucas