The way to Establish and Handle Dogwood Pests


Whether or not you’re a grasp gardener or a botanical layperson, it’s simple to see {that a} dogwood could be very engaging. Sadly, a plethora of pests may also discover that very same Cornus to be fairly interesting.

A close up vertical image of white dogwood flowers growing in the garden pictured on a soft focus background. To the center and bottom of the frame is green and white printed text.

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An individual might snap a photograph or simply take within the view, however pests have a tendency to indicate their appreciation in additional… malevolent methods.

From protecting the floor of the tree to consuming its tissues outright, a pest will benefit from a dogwood’s vulnerability and go away the tree trying broken or sick.

“However how do I forestall this?” “How can I take care of an infestation-in-progress?” “Is all hope for my dogwoods misplaced?”

The hows of pest prevention and administration are coated on this information. As for the hope?

After absorbing the data supplied right here, you’ll be well-equipped to present your dogwoods a combating likelihood, I can promise you that.

Listed below are these pesky foes that you just’ll find out about up forward:

Earlier than we start, it’s necessary to reiterate {that a} wholesome dogwood is extra resilient towards pests than an unhealthy one.

Subsequently, you must attempt to domesticate and care to your dogwoods as healthfully as potential. For a decreased danger of infestation, attempt your darndest to present a dogwood precisely what it requires for optimum well being.

An added plus of stopping pests? They will’t vector illnesses that might hurt your dogwoods. Speak about a two-for-one!

1. Dogwood Borers

Once we discuss dogwood borers, we’re referring to the larval type of Synanthedon scitula.

Coming into the tree by way of wounds or different bark openings, the larvae go away sawdust-esque frass of their wake as they feed on the internal bark and cambium.

This feeding can go away the tree in dire straits: leaves can redden and prematurely drop, bark close to the borers’ entry factors sheds off, and branches typically die because the cambium is destroyed.

Younger timber can perish inside a season or two, whereas extra mature timber can survive, albeit with tough knots and decreased vigor.

A close up horizontal image of a dogwood borer moth on the surface of a leaf.
Picture by Thomas Shahan, Wikimedia Commons, through CC BY-SA.

These larvae are a bit over half an inch lengthy, with a reddish-brown head and a whitish to cream-colored physique.

The clear-winged, wasp-like grownup moths are available at half an inch in size, with a yellow-banded and blueish-black physique.

Over a several-month interval from spring to fall, the feminine adults lay eggs on the bark, which units the stage for the larvae to hatch, enter the tree by way of its openings, feed, overwinter of their feeding tunnels, after which feed once more earlier than they pupate.

Correct cultivation and wound avoidance will assist forestall infestations of those pests.

For administration of a present infestation, prune away affected branches in late winter, when the moths are inactive.

You can even insert a thin wire into the borers’ feeding tunnels, which is able to crush them.

A close up horizontal image of the base of a tree suffering from borer damage.
Picture by James Solomon, Wikimedia Commons, through CC BY-SA.

For extra drastic management, you possibly can spray permethrin on the trunk, root collar, main branches, and bark wounds. Start in early Might, and reapply each three weeks as much as 4 occasions.

Useless timber needs to be excavated and pitched. Be at liberty to attempt once more with hybrid crosses of C. florida and C. kousa from the Stellar sequence, that are extremely proof against dogwood borers.

2. Dogwood Membership Gall Midges

Resseliella clavula is a small, but important foe of the dogwood.

The grownup fly, a couple of sixteenth of an inch lengthy, lays eggs inside a dogwood’s tiny terminal foliage in late spring.

A close up vertical image of a dogwood tree suffering from gall.
Picture by Northcut, Wikimedia Commons, through CC BY-SA.

Upon hatching, the orange larvae eat their manner by way of shoots, and tubular, swollen galls kind in response alongside stems or at stem ideas.

Past the gall on a shoot, stem tissue can die, whereas leaves can wilt and warp. With a big midge infestation, a tree will be left deformed.

Administration-wise, your finest wager is to prune away and destroy any infested shoots a number of inches beneath the gall.

3. Dogwood Sawflies

Similar to with the above-described pests, the hazard of a Macremphytus tarsatus lies in its younger.

Rising in late spring, the slender black adults lay as much as 100 eggs in a single leaf, inserting them subsequent to the leaf veins in rows of small brown bumps.

A close up horizontal image of a dogwood sawfly larva on a stem, pictured on a soft focus background.

The colour of the caterpillars that hatch out varies, relying on their developmental stage.

First-instar caterpillars are small and translucent yellow, second-instar caterpillars are coated with a white wax, and final-instar caterpillars are a black-spotted yellow.

As you’ve most likely gleaned from Eric Carle’s “The Very Hungry Caterpillar,” larvae corresponding to these will eat lots of leaf tissue, typically to the purpose of great defoliation.

After they’ve molted into their last larval stage, the caterpillars will stop consuming and burrow into wooden for overwintering earlier than they emerge as grownup sawflies come spring.

When the caterpillars are lower than an inch lengthy, sprays of insecticidal soaps or horticultural oil will be efficient.

In any other case, you must stick to handbook elimination: both dislodge them by shaking the tree or take away them by hand. Upon elimination, drown the pests in soapy water or crush them beneath your heel.

A close up of a bottle of Monterey Horticultural Oil isolated on a white background.

Monterey Horticultural Oil

For a horticultural oil focus that’s accredited for natural gardening, Monterey sells some in quart- and gallon-sized bottles through Arbico Organics.

4. Dogwood Twig Borers

Also called Oberea tripunctata, the dogwood twig borer doesn’t solely assault species of Cornus – willow, viburnum, and azalea are however a number of of its different targets.

A bit over half an inch in size, grownup twig borers are skinny, cylindrical, brownish-orange beetles with lengthy, darkish antennae and darkish brown to black heads.

A close up horizontal image of a dogwood twig borer on a leaf pictured on a soft focus background.

The visibly segmented larva measures as much as an inch lengthy, with a brown head and pale yellow physique.

In late spring, the adults chew twin traces of holes across the ideas of newly-grown stems, and lay an elongated egg in between the girdled rings.

Upon hatching, the larvae bore their manner additional into the stems, leaving a sequence of holes operating down the stem’s aspect as they feed.

This feeding wilts and kills the foliage above the tunneling, and the stem may even break off at factors the place the larvae girdle the stem from the within.

A close up horizontal image of a dogwood twig borer on the surface of a leaf.
Picture by Gordon C. Snelling, Wikimedia Commons, through CC BY-SA.

Come spring, after overwintering within the hollowed-out stems, the larvae both proceed to feed for one more yr or pupate into the grownup stage. By late spring, the adults emerge, and the cycle continues.

Sprays of a pyrethroid insecticide in late spring can forestall these pests from laying eggs, whereas stems which have been tunneled into needs to be pruned in early summer season if you discover the resultant leaf wilt.

Make your pruning cuts beneath the larva’s present location inside the twig, and burn your pruned twigs to forestall a twig borer comeback.

5. Flatheaded Appletree Borers

Upon first seeing what Chrysobothris femorata seems to be like, I used to be reminded of the notorious chestbursters from the “Alien” franchise.

With a tannish-white, segmented physique and a comparatively huge thorax beneath its black head, this pest can tunnel its manner by way of a dogwood’s tissues like a Xenomorph larva by way of Government Officer Kane.

Picture by James Solomon, USDA Forest Service, Bugwood.org, through CC BY-SA.

After the sunflower seed-esque grownup beetles lay their eggs within the tree’s bark all through the summer season, the larvae emerge from the eggs and eat their manner by way of the bark and cambium, creating galleries that girdle the tree and disrupt vascular tissues.

Infestation signs manifest as foliar wilt and necrosis, department dieback, and darkened bark that secretes a nasty white liquid.

Moreover, the feeding tunnels inside the tree can grow to be sunken and obvious, and the bark above can die and fall away.

Small younger timber can simply die from an infestation of those pests, the well being and look of extra mature timber can take a success, and troubled specimens will be left particularly susceptible to pathogens.

These pests are significantly keen on unhealthy timber, so it’s additional necessary to domesticate your dogwoods correctly and defend them from damage.

Make sure to prune useless and broken branches, that are potential entry factors for the pests.

Picture by Joseph Berger, Bugwood.org, through CC BY-SA.

Wrapping dogwood trunks with a protecting protecting from March to September can deter egg-laying.

Many supplies work, corresponding to mosquito netting, fine-mesh {hardware} material, and even layered newspaper!

Upon noticing the grownup beetles, spraying the trunk and main branches with a pyrethroid insecticide will be useful.

This may management the adults however not the burrowing larvae, so it pays to strike quick.

For heavily-infested timber, a immediate elimination and burning is so as. It might be tragic, however no less than any of the infesting pests will likely be killed as properly.

6. Vertebrates

A plant that attracts wildlife into your backyard isn’t all the time a nasty factor, as a inhabitants of numerous species can point out a wholesome ecosystem.

Nonetheless, if stated wildlife munches on foliage, or consumes fruit that you just your self meant to reap, then that’s when you must take into account taking motion.

Quite a lot of critters can feast on dogwoods.

Foxes, mice, skunks, chipmunks, black bears, songbirds, turkeys, beavers, deer, and rabbits eat the fruits, whereas the latter three additionally browse the leaves and younger sprouts.

A close up horizontal image of a buck deer with large antlers in a snowy landscape.

Whereas managing creepy-crawly pests is normally a cold-blooded and murderous follow, it’s necessary to attempt to management most increased types of life with a little bit of empathy, through nonlethal strategies.

Treating your yard prefer it’s open season can land you in authorized hassle for those who hurt any protected species, to not point out flip your abdomen.

Birds are finest managed through scare techniques which might be cycled by way of weekly, in order that they don’t develop smart to your tips.

Reflective surfaces, balloons with eyes drawn on them, scarecrows, rubber snakes, and pretend birds of prey – visually, you’ve got loads of choices.

Sound-wise, loud noises are the important thing, whether or not it’s with wind chimes, banging pots and pans collectively, and even one thing higher-tech like a noise machine.

A close up horizontal image of a collection of colorful songbirds on the branch of a tree in winter.

You’ll want some bodily deterrents for the non-fliers, although.

Small mammals like squirrels, beavers, and foxes usually require safety through a per-planting perimeter of ultra-fine hen wire or flimsy {hardware} material, buried a pair inches beneath the floor to discourage tunneling.

Bigger mammals corresponding to deer and black bears want bigger, probably electrified fencing round your whole property.

For any of the aforementioned critters, you possibly can all the time complement piecemeal with some species-specific repellents, relying on which specific ones plague your dogwoods.

7. Scale Bugs

Quite a lot of scale bugs can infest your dogwoods, corresponding to armored oystershell scale and brown delicate scale. Scale range in shade, and are small, oval-shaped pests with no seen legs.

Gentle scale possess a thick, waxy coating, measuring an eighth- to a quarter-inch lengthy.

With a clean, cottony, or waxy coating, these pests excrete honeydew: a dangerous, ugly, and ant-attracting substrate for sooty mould.

Armored scale species are smaller, coming in at lower than an eighth of an inch lengthy. Flaunting their trademark hardened shells, these pests lack the honeydew excretion of their delicate relations, fortunately.

A close up horizontal image of scale insects infesting the branch of a tree.

With populations that may quickly develop after a pair seasons, scale bugs feed on the sap that they extract with their piercing-sucking mouthparts.

Infested dogwoods can endure with chlorotic and prematurely-dropped leaves, heavily-infested shoots can perish, and the complete tree’s development price can considerably gradual.

If small, remoted parts of the tree’s construction are densely filled with these pests, prune them away. Moreover, you possibly can prune inside the cover to extend the penetration of scorching daylight.

Bodily, you possibly can spray the tree with sturdy bursts of water, or manually scrape away small pest infestations with a butter knife.

Thorough springtime purposes of horticultural or neem oil, each earlier than bud break and after flowering, can kill adults and eggs alike.

Parasitic wasps and ladybugs are efficient predators of scale, and including store-bought reinforcements to the already-present ones in your panorama generally is a sensible transfer.

However not all the time, as introducing non-native species – ladybugs particularly – will be dangerous.

Be taught extra about scale bugs and the way to take care of them in our information.

Canine-Uninterested in Dogwood Pests?

You then’ve obtained a real pal on this information. Be at liberty to refer again to it everytime you want to refresh your dogwood pest fight abilities!

A horizontal image of a white dogwood tree in full bloom growing in the garden.

However simply as black belts hone their skills past the purpose of mastery, you have to achieve this along with your pest management administration.

One great side of gardening is that you just’ll by no means know all of it, so the tutorial journey is certain to by no means finish!

Have pest management questions? Want to share the small print of your administration successes and failures? Put ’em into the feedback part beneath.

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