Black spots on pears: causes and treatment methods

There are a myriad of reasons why pears can turn black. Pests and diseases caused by fungi and bacteria can irreparably ruin the harvest. Fruit turning black can also be due to nutritional deficiencies and unfavorable weather conditions. In this case, timely diagnosis is useless; only comprehensive preventative measures can prevent the situation.

Why do pears turn black?

Unharvested pears turning brown mean a complete loss of the harvest. You should neither eat nor store spoiled fruit. The only solution is to determine the cause of the problem and learn what to do if pears are turning black right on the tree.

Scab

Scab is a fungal disease that causes black spots and blotches to appear on the above-ground parts of the tree. These spots first cover the flowers and leaves, and then affect the fruit. Scab not only damages the harvest but also the tree itself, causing the bark to crack.

Favorable factors for the development of scab:

• rainy weather;
• strong thickening of the crown;
• trees that are too young or too old have a weakened immunity to scab;
• cultivation of varieties that are genetically unstable to scab (Phelps, Marianna, Forest Beauty).

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Fungal spores survive in fallen leaves and pruned branches. After overwintering under snow, they begin their destructive activity in the spring. To prevent scab from developing, all biodegradable debris must be removed and destroyed.

Preventative spraying is carried out regularly throughout the growing season. Recommended products:

• in early spring – with Bordeaux mixture;
• before flowering and after flowering - with "Horus" or "Topaz".

Moniliosis

This disease is also known as fruit rot. It primarily affects pear and apple trees. It's difficult to tell if a tree is infected until the fruit appears.

How to tell if a pear is infected with moniliosis:

• small brown spots appear on the fruits;
• in a very short time, the spots cover the entire fruit, its pulp turns brown, softens, and becomes unsuitable for consumption;
• after 10-12 days, the affected fruits become covered with concentric yellow-beige circles – fungal spores are developing in them;
• The damage also affects the branches – they dry out and die.

Fruit rot is a dangerous, rapidly spreading disease. If it appears in an orchard, it can infect all trees. Infection occurs through the transfer of spores and through contact between diseased fruit and healthy ones.

Factors contributing to the development of fruit rot:

• damage to the integrity of the fruit – this can be caused by birds, hailstones, insects;
• humid (75-80%) and warm weather (+24..+28°С);
• thickening of plantings - the fungus develops well in the shade.

Moniliosis, or fruit rot, is treated like scab with Horus, Topsin, Fitosporin, and other fungicides. Pest control is also necessary, as is the treatment of the infection.

Spraying procedure:

• before bud break – with 1% Bordeaux mixture;
• twice in spring with an interval of 2 weeks – with any fungicide;
• a month before harvesting - with iodine solution (10 ml of iodine per bucket of water);
• 3 days after spraying with iodine, repeat.

Codling moth

The pear codling moth is considered the most devoted pest, attacking only pear trees. The moth, gray with a silvery edge, is up to 2.2 cm long and prefers early varieties. It lays eggs directly on the fruit's skin. The moth lives for 15 days, but during this time it can lay 50-70 eggs. It only takes 5-10 moths to completely destroy the fruit on 1-2 mature trees.

Once formed, the larva emerges from the egg and penetrates the fruit, chewing its way through the flesh. It crawls toward the seeds, which are its primary food source. The caterpillar feeds on the seeds for a month. As a result, the pear fruits darken, rot, and fall off.

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How to fight codling moth:

1. They set up light traps for butterflies. The winged insects fly toward the light source and become trapped in containers filled with kerosene or soap.
2. Traps filled with sweet syrup or whey are hung on branches.
3. Covering tree trunks with sticky tape to trap larvae. The strips are cut from rags or cardboard, and the sticky layer is made of non-drying glue or grease.
4. Spraying should be done just before the butterfly flight or as soon as it begins. Repeat spraying should be done after 10 days. Use "BI-58 Novyi," "Ditoks," and "Binom" for treatment. It is recommended to mix chlorophos and karbofos with copper oxychloride for a stronger effect.

Weevil beetles

The pear weevil is a small beetle that becomes active in the spring. After emerging from hibernation, the pest begins not only to feed but also to reproduce. Pear weevils are copper-red in color with a greenish sheen. The beetle is 8-10 mm long.

Weevils damage virtually every part of the tree, primarily buds and flower buds, and less commonly, leaves and shoots. The beetle larvae are legless, white-yellow worms up to 8 mm long. They gnaw through the fruit, penetrating it and eating away all the pulp from the inside.

Signs of weevils in the garden:

• damaged buds and buds - it is clear that they have been gnawed by insects;
• gnawed leaves;
• spots appear on the fruits.

How to fight:

1. Spray with a chamomile infusion. Prepare the solution by steeping 150 grams of chamomile flowers in a bucket of water. Let it steep for 24 hours, add soap, and apply to the crown. You can also use infusions of garlic, pine or spruce needles, onion peels, or tomato tops.
2. Beetles are collected by hand. They are covered with plastic or other material and shaken off the insects. Beetle collection should begin before flowering.
3. They attract birds to the garden, as they readily eat the beetles. Wasps and ants are also natural enemies of weevils.
4. They are treated with chemicals: Fufanon, Fitoverm, Karate.

Old trees

Black spots often appear on older trees. This is due to a weakened immune system—it declines with age, and the tree can no longer fully resist infections. It often falls prey to fungi and bacteria. On older pear trees, the fruit begins to rot from the stem. By the time they're fully ripe, at least 50% of the flesh has rotted.

It's practically impossible to get rid of this affliction. The tree has aged, and it's time to replace it with a new one. While the pear tree is still alive, there's another way to save the fruit: to prevent it from rotting, pick it before it ripens. The pears are picked unripe and laid out on a canvas to ripen. Unripe fruit can also be used to make compotes and preserves.

How to prevent rot

To prevent pear fruit from becoming spotted or rotting, a comprehensive range of preventative measures must be taken. This is the only way to protect the tree from any harmful factors.

General rules for combating diseases and pests:

• Spraying is carried out in the morning or evening hours, when it is not hot;
• If it rains soon after crown treatment, you will have to repeat it as soon as favorable weather conditions arise;
• For spraying, use devices with a fine spray nozzle attached to the end of a long tube;
• When spraying trees with chemicals, you must wear protective clothing and a respirator.

Proper agricultural technology

A strong and healthy tree that receives the right amount of water and fertilizer is much less likely to be attacked by microorganisms and insects.

What does a tree need for normal development and strong immunity:

1. Throughout the summer, pear trees require abundant and regular watering. The maximum interval between waterings is 30 days, or 2 weeks in hot weather. The recommended watering rate is 2 buckets of water per square meter of trunk area.
2. The tree should be planted so that its root system has sufficient space to develop. Avoid planting pear trees where they will have to compete for moisture and nutrients. Maintain a 5-meter distance between trees.
3. Tree trunks are mulched to prevent weeds and grasses from growing there. Firstly, they absorb moisture and nutrients, and secondly, they can attract insects and serve as sources of disease.
4. Proper fertilization. Both under- and over-fertilization can negatively impact tree health. Excessive fertilization can cause young branches to stretch, and delayed flower bud development. Fertilize every 3-4 years.

Chemical treatment

Today, specialized agricultural stores offer a wide range of fungicides and insecticides designed to combat pests and diseases. They are used preventatively or as treatments as problems arise.

To prevent damage to pear fruits, it is necessary:

• spray trees with fungicides in spring and autumn;
• Before and during flowering, treat with insecticides to prevent the appearance of larvae in the fruits.

Best drugs:

• Bordeaux mixture;
• Horus;
• Fitoverm;
• Fitosporin.

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The most popular product, Bordeaux mixture, has a broad spectrum of action. It's a blue liquid compound consisting of lime, copper, and water. It simultaneously combats both diseases and pests that overwinter in the bark.

Folk remedies

There are dozens of recipes used to treat fruit trees. Fruit rot is prevented by killing bacteria, fungi, and insects.

The sooner treatment begins, the higher the chances of success. And it's best to begin treatment before problems arise.

Folk remedies for fruit rot caused by pear diseases:

1. Mix 40 g of citric acid with 25 g of ferrous sulfate in a bucket of water. The solution is effective for two weeks.
2. Dissolve 6 kg of compost and 150 g of ferrous sulfate in a bucket of water. Pour this solution into the tree trunk circle.

Folk remedies for pests that spoil pear fruits:

1. Mix 10 teaspoons of dishwashing liquid, the same amount of vegetable oil, and rubbing alcohol in a bucket of water. Spray the tree with the solution daily for 3-4 days.
2. Grate 250 g of soap—either laundry soap or tar soap. Dilute it in 10 liters of water. Pour in a glass of vegetable oil and shake. Spray the prepared solution onto the crown of the tree.

Solutions of colloidal sulfur and laundry soap, nettle infusion, and herbal infusions such as chamomile, yarrow, dandelion, tobacco dust, and garlic also help fight pests.

Repellents plants

It's recommended to plant insect-repellent plants in the garden. These phyto-weapons are completely harmless and effective. Many repellents are quite attractive and also serve as a decorative element in the garden.

Repellent plants stupefy and repel insects, including butterflies that lay eggs on fruit trees:

• fennel polypodium;
• tansy;
• sagebrush;
• mint;
• carnation;
• coriander;
• rue;
• lavender;
• calendula;
• thyme and others.

Plants can be used not only to repel pests but also to attract them. The best option for this purpose is nasturtium. This low, attractive plant with light green leaves and bright orange flowers attracts insects. These can be collected or destroyed along with the nasturtium.

Disease prevention

To get a good pear harvest, you need to care for your tree throughout the season. Spring preventative maintenance is especially important.

Preventive measures:

1. Timely pruning. In late winter, before the buds swell, perform sanitary pruning, removing broken, frozen, dry, and diseased branches. Prune back to healthy wood. Dispose of all pruned material.
2. All mummified fruits are destroyed, as they contain fungal spores.
3. The crown is thinned to ensure even light and ventilation across the branches. A properly formed crown will allow the branches and fruit to dry more quickly after rainfall.
4. In case of large harvests, the fruits need to be thinned out, leaving only the largest ones.
5. Pears are picked carefully. It's important not to damage either the branches or the fruit during harvesting. Only completely healthy and undamaged fruits are stored.
6. In early spring, spray the trees and the surrounding soil with Bordeaux mixture. Repeat the procedure at 2-3 week intervals until the fruit ripens.

Typical mistakes gardeners make

If the fruit of a fruit tree becomes spotted, it means a cultivation error was made at some point. Most cases of damage can be prevented with timely action.

Mistakes that lead to blackening of fruits:

• the crown is pruned at the wrong time;
• violate the watering regime;
• not fed enough;
• Place the affected parts of the tree on compost;
• do not dig up the tree trunk circle in the fall;
• do not remove fallen leaves;
• buy seedlings of varieties that are not resistant to diseases;
• do not disinfect the instrument used for pruning.

For a gardener who has invested their time in growing fruit, it's especially frustrating when the fruit, almost ready for harvest, spoils. To prevent this, it's essential to take care of its preservation well before harvest.