American Basswood

Japanese beetles are metallic green-and-copper beetles about half an inch long that emerge in early summer and feed for six to eight weeks. They feed in aggregating masses - one beetle's feeding releases a scent that draws in more - so a plant goes from untouched to covered in a couple of days. They chew the soft tissue between the leaf veins and leave the veins standing, so the leaf ends up as a brown lace skeleton, and they shred open flowers and sometimes ripening fruit as well. They work the sunniest upper parts of a plant on warm afternoons. The white C-shaped grubs spend the rest of the year in turf and pasture soil eating grass roots, and the adults then fly in from wherever they hatched, which can be some distance away.

Watch for: Clusters of shiny metallic beetles massed together on the upper, sunniest foliage and down inside open blooms, heaviest on warm sunny afternoons from around late June. Leaves reduced to lace, with the veins left intact and the tissue between them gone - unmistakable, and quite different from the ragged chewing of a caterpillar. Ragged, chewed petals and blooms that never open properly. Beetles that let go and drop straight to the ground when you disturb the plant. Feeding damage on ripening fruit, on the plants they also take fruit from. Whole branches going brown and lacy at the top of a plant while the shaded lower growth stays untouched.

Prevent: Hand-picking is genuinely the main defense in a home garden. Go out in the cool of the morning while the beetles are sluggish, hold a tub of soapy water underneath, and knock them in - they drop when disturbed, so most fall straight into it. Do it daily through the flight: because the beetles call each other in, taking them off early stops a plant becoming a beacon. Do not put pheromone or lure traps anywhere near the garden - they demonstrably pull in far more beetles than they catch. And do not count on lawn grub control: milky spore has performed poorly and inconsistently in field trials across most of the US, and treating your own turf does not reduce the adults feeding on your plants, because they fly in from surrounding properties. Where it is practical, row cover or netting through the peak flight excludes them outright. Otherwise riding out the six-to-eight-week wave is a legitimate strategy, since most established plants absorb the damage.

Treat: Persistent morning hand-picking into soapy water is the most effective home control there is, and on a vigorous established plant the damage is usually cosmetic and needs nothing else. Neem deters feeding rather than killing, and has to be reapplied. For heavy pressure, spinosad or a targeted insecticide labeled for the plant will work - but time any spray away from bloom and apply it at dusk to protect bees, and observe the pre-harvest interval on anything you eat. On flowering plants, some gardeners simply shear the blooms off for a couple of weeks and let the plant rebloom once the wave has passed, which removes the lure as well as the damage. Young plants and young trees are the ones worth defending: a mature tree or an established vine tolerates several weeks of leaf loss without lasting harm.

Linden is one of the beetles' most preferred trees and the top of the crown is routinely laced by mid-July. Ride it out on a mature tree - the damage is cosmetic and the leaves are already made. Do NOT use a soil-applied systemic here: basswood is one of the heaviest bee-forage trees there is, and a systemic ends up in the nectar. Hand-pick what you can reach on a young tree.

Deer are the largest garden problem across much of the country, and where pressure is high they set the limit on what you can grow at all. They browse at night and around dawn and dusk, taking tender shoots, leaves, buds, flowers, and fruit within about five feet of the ground, and they come back night after night to anything they have found and liked. Because they have no upper incisors they tear rather than cut, leaving ragged stem ends - that is how you tell deer damage from a rabbit's clean angled cut. In fall, bucks rub their antlers on young trunks and can strip the bark right around a stem, which kills a young tree outright. Palatability varies enormously between plants and between seasons: a herd short of food in late winter eats things it ignores in June, and no plant is truly deer-proof.

Watch for: Growth cleanly missing overnight, with the plant browsed back to a level line about as high as a deer can comfortably reach. Ragged, torn stem ends rather than the clean angled cut a rabbit leaves - the single most reliable identifier. Buds and flowers gone while the foliage below is untouched, since deer often take the best part first. Hoof prints and droppings in soft ground near the damage. Repeat visits, with fresh damage each morning once a planting has been found. On young trees, shredded and stripped bark and broken low branches in autumn - that is antler rubbing rather than feeding.

Prevent: Fencing is the only thing that reliably works. Eight feet is the standard for excluding deer, or two parallel four-foot fences a few feet apart, which they will not jump because they cannot judge the landing. Short of that, cage individual plants: a sturdy wire cage or trunk guard around every young tree, left on until the trunk is thick and the canopy is above browse height, prevents both browsing and antler rubbing and is the single highest-value thing you can do for a young tree. Repellent sprays do help at moderate pressure, but they wash off and deer habituate, so reapply after rain and rotate between different types through the season. Motion-activated sprinklers, scent deterrents, and noise devices work for a while and then stop. Siting matters too: plants close to the house, in daily traffic, and screened behind other planting get browsed less than the same plant out at the boundary.

Treat: There is no chemical fix, only exclusion and recovery. Get physical protection up immediately after the first damage, because deer return to a known meal, and reinforce or rotate whatever you were relying on before. Most plants regrow from browsing if the crown and roots are intact - feed and water a grazed plant and protect the regrowth while it comes back. What does not recover in the same season is anything whose buds or flowers have been taken, and a young tree whose bark has been rubbed right around the trunk is usually lost. Where deer pressure is genuinely heavy, the honest answer is to fence properly or to grow the plants deer leave alone, rather than to keep replacing losses.

Basswood is among the most preferred deer browse in eastern North America - so preferred that in overbrowsed woodlands it stops regenerating altogether and the canopy trees are never replaced. Treat a cage as part of planting the tree, not as an option, and leave it on until the lowest branches are above reach and the trunk is too thick to rub.

Aphids are small soft-bodied sap-suckers - green, black, gray, pink, or waxy white, and mostly wingless - that gather in dense colonies on the tenderest new growth: shoot tips, buds, and the undersides of young leaves. They breed extremely fast in mild weather, so a few can become hundreds inside a week. Their feeding curls and distorts soft growth, and the sticky honeydew they excrete coats everything below and turns black with sooty mold. Ants often farm and defend the colonies for that honeydew. A few aphids are normal on almost any plant and a healthy plant shrugs them off; only dense, persistent colonies do real damage, and some aphids also spread plant viruses as they feed.

Watch for: Dense clusters of tiny insects packed onto shoot tips, flower buds, and the undersides of young leaves. Curled, cupped, or distorted new growth that never opens properly. A sticky shine on the leaves - and on whatever sits under the plant - that later goes black with sooty mold. Tiny white cast skins left behind where a colony has been feeding. Ants running steadily up and down the stems, which is often the first thing you notice. Mottled, streaked, or misshapen leaves that do not grow out can mean a virus the aphids brought with them rather than the feeding itself.

Prevent: Go easy on nitrogen: the soft, lush growth that heavy feeding produces is exactly what aphids breed on. Check new growth once a week through spring and early summer so you catch colonies while they are still small, and rub the first few out with your fingers. Leave flowering plants nearby and skip broad-spectrum sprays - ladybugs, lacewings, hoverflies, and parasitic wasps do most of this work for free, and they only stay if there is something for them to eat. Keep ants off the plant where you can, since they protect aphids from those predators. Water steadily so plants are not stressed, and check any new plant over before you bring it home or move it indoors, since aphids usually arrive on something else.

Treat: Knock the colonies off with a hard jet of water and repeat every few days - on most plants that alone ends it. Pinch out or prune off the worst-infested tips rather than treating the whole plant. If colonies keep rebuilding, spray insecticidal soap or horticultural oil directly onto the insects, covering leaf undersides, and repeat weekly until they are gone; treat early or late in the day, and never spray a wilted or heat-stressed plant. Avoid broad-spectrum insecticides - they kill the ladybugs, lacewings, and parasitic wasps that were about to solve the problem for you, and aphid numbers usually come back worse afterward. Anything you spray must be labeled for the plant you are treating; follow that label and observe its pre-harvest interval. On anything you eat, wash leaves, heads, and buds well before use, since aphids hide down in crowns, folds, and tight growth.

The linden aphid is the reason nobody parks under a linden. It does the tree little harm but rains honeydew for weeks, glazing everything below and turning it sooty black, and it will spoil any flowers you meant to dry for tea. Nothing sprayed on a big tree fixes it and predators usually catch up by midsummer - so treat it as a siting rule, and pick your tea flowers from a clean branch or a clean year.

Leaf scorch is not a disease and there is nothing to spray for it. It is what happens when a leaf loses water faster than the roots can replace it: the tissue farthest from the veins - the margins and the tips - dries out first and turns brown and papery, and the browning works inward while the rest of the leaf stays green. Hot sun, dry soil, drying wind, heat reflected off paving or a wall, a small or damaged root system, and a plant sited somewhere sunnier or drier than it wants are the usual causes, singly or together. It also happens in winter on evergreens, when bright sun and wind pull water out of the leaves while the ground is frozen and the roots cannot resupply. Shade and woodland plants, shallow-rooted plants, and anything recently planted scorch most easily.

Watch for: Browning that starts at the leaf edges and tips and spreads inward, with a fairly sharp line between the crisp brown tissue and the green that is still healthy. Leaves and fronds going dry, papery, and crisp rather than soft, yellow, or spotted - that is what separates this from a fungal problem. Damage worst on the side of the plant facing the sun or the prevailing wind and on the most exposed upper leaves, while the shaded interior stays fine. Symptoms appearing sharply after a heat wave, a dry spell, or a bright windy week in winter. Whole leaves or fronds shed early as the plant cuts its losses.

Prevent: Site the plant where it actually wants to be. This is a placement problem far more often than a watering problem, and a shade plant in hot afternoon sun will scorch every summer however much you water it. Give shade and woodland plants part-to-full shade and shelter from hot afternoon sun and drying wind. Keep the root zone consistently moist and mulch it well with leaf litter or another organic mulch, which holds water and keeps the roots cool - the single most useful routine step. Water deeply and thoroughly during dry spells rather than little and often, so moisture reaches the whole root zone. Pay particular attention through the first year after planting, when the root system is small and cannot keep up with the leaves. On evergreens in cold regions, make sure the plant goes into winter well watered, and keep it out of bright, windy, exposed positions.

Treat: Water deeply, mulch, and improve the shade - that is the whole treatment, because there is nothing here to kill. Leaves that are already scorched will not recover, so trim off badly browned foliage or fronds for appearance if you want to; the crown and roots are usually unharmed and push out fresh growth once conditions improve. On a plant that scorches badly every year the answer is to move it rather than to keep watering harder, because the siting is what is wrong. Some plants respond well to being cut back hard, which brings a clean flush of new foliage. And on plants that naturally die back or brown off late in the season, scorching at the end of a dry summer is normal and needs nothing at all.

Basswood's huge soft leaves scorch readily, and browned margins with early August leaf drop are the standard sign of a tree on too dry or too exposed a site. Widen the mulch ring, take the turf out from under the canopy, and soak the root zone deeply through dry spells. A basswood that scorches every year is telling you the site is wrong.

A soil fungus (Verticillium dahliae and relatives) that enters through the roots and grows upward inside the water-conducting tissue, plugging it from within. The plant is not being eaten or rotted, it is being cut off from its own water supply, which is why the signature symptom is one branch or one side wilting and browning while the rest looks perfectly healthy. Cut into affected wood or stem and the tissue is streaked olive-green, grey or brown. The host range is enormous - maples, redbud, olive, tomato, potato, pepper, eggplant, strawberry and many more - and the fungus survives in soil for years as tough resting structures, so infected ground stays infected. Grasses and conifers do not get it.

Watch for: One branch, one limb or one side of a plant wilting, yellowing and browning in summer while the rest carries on normally - the lopsided pattern is the tell - and leaves that wilt and then hang on rather than dropping cleanly. Cut into affected wood and look for olive-green, grey or brown streaking along the grain; in a cut vegetable stem it shows as a ring of discolored dots. On vegetables, lower leaves yellow in a wedge from the margin inward, and the plant wilts at midday but recovers overnight in the early stages.

Prevent: There is no way to sterilize garden soil of it, so prevention is plant choice and plant vigor. Do not replant a susceptible species where one has already died of it. Grasses, conifers, ginkgo, hawthorn, hornbeam, honeylocust, oak and beech do not get it, and many vegetable varieties carry bred-in resistance - the V in a VFN code on the seed packet. Rotate susceptible vegetables on a long cycle and keep them off ground where the disease has shown. Buy clean stock, avoid wounding roots with spades and machinery, and keep woody plants steadily watered, mulched and only lightly fed, because a vigorous plant walls the fungus off far better than a stressed one.

Treat: There is no cure and nothing to spray. On a tree or shrub the aim is to keep it alive long enough to compartmentalize the fungus, which many plants manage for years: prune out dead and wilting branches well below the discolored wood, sanitize the pruners between cuts, water deeply through dry spells, mulch, and feed lightly rather than pushing it with a heavy feed. On vegetables, pull and bin affected plants rather than composting them, and move that crop to clean ground or to containers of fresh mix. Do not replant the same species where one has died.

Uncommon on basswood and rarely fatal - the tree usually walls the fungus off and carries on. If a single limb wilts and dies in midsummer, prune it out well below the streaking, sterilize the saw, and concentrate on watering and mulching rather than on any treatment.