In Iowa, the foliage of the river birch (Betula nigra) often turns a sickly yellow-green. The yellow-green foliage is due to a deficiency of iron. The problem is referred to as iron chlorosis. (A close examination of chlorotic leaves…
Broken or damaged tops are common on young trees due to wind, ice, wildlife, winter dieback or equipment injury. While this damage can affect tree form, most young trees recover well if corrective pruning is done early. The primary goal is to…
Oedema is probably responsible for the lesions on the undersides of the ivy geranium leaves. Oedema is not caused by an insect or disease pathogen. It is a physiological problem. Oedema is most often encountered in greenhouses…
The brown streaks in the apples are probably due to the apple maggot. The apple maggot is the most serious insect pest of apples in Iowa. Apple maggot damage appears as knobby, misshapen fruit with small pits or blemishes on the fruit…
The hair-like growths are likely galls. Galls are abnormal growths of plant tissue induced to form by mites, insects, or other small organisms. The hair-like gall on the maple leaves is probably the maple spindle gall.
The gray-green patches are probably lichens. Lichens are unusual organisms. They consist of two unrelated organisms, an alga and a fungus. These two components exist together and behave as a single organism. The agla provides food via…
The large, green caterpillars are probably tomato hornworms. Tomato hornworms are bright green, up to 4 to 5 inches long, and have red or black, horn-like projections on their rear ends. After feeding, hornworms move to the soil where…
The foam-like masses in the dogwoods were probably created by the dogwood spittlebug. The dogwood spittlebug is one of several species of this commonly recognized group of sap-feeding insects. Spittlebugs are familiar because of the…
The small, black beetles are likely sap beetles. They are also known as picnic beetles or picnic bugs. Sap beetles commonly feed on overripe or damaged fruits and vegetables in the garden.
The small, brown spots are likely due to iris leaf spot. Iris leaf spot is a common disease of bearded irises. The disease is caused by the fungus Mycosphaerella macrospora. The first symptom of iris leaf spot is the appearance of…
The wart-like growths on the hackberry leaves are galls. Galls are abnormal growths of plant tissue induced to form by mites, insects, or other small organisms. They are quite common on trees.
The white, fuzzy objects on the branches of your maple tree are wooly alder aphids. (The insect is also known as the maple blight aphid.) Wooly alder aphids feed on the sap of maple trees from bud-break until late June. Then…
The growth on the trunk of the maple tree is likely a burl. Burls are abnormal swellings or growths that develop on the trunks and branches of trees. Burls can be found on deciduous trees and evergreens. The exact cause is…
The large, hard growth is probably crown gall. Crown gall is caused by the bacterium Agrobacterium tumefaciens. The bacterial disease can infect roses, grapes, apples, raspberries, willows, euonymus, and many other woody…
The Austree is a hybrid willow. Its parents are the corkscrew willow (Salix matsudana) and white willow (Salix alba). While Austrees are fast growing trees, insects and diseases can be problems. Because of…
Hardneck cultivars of garlic will produce a scape or flower stalk from the center of the leaves in mid-to-late May. Removing the scape is advised as it will help the bulb grow larger because the plant will put energy into bulb production…
Jostaberries are a cross between black currants and gooseberries. Plants are vigorous and may grow to a height of 6 to 8 feet. Jostaberry fruit are similar in size to gooseberries and black in color. Plants possess excellent…
There are a number of vegetables that are relatively easy to grow. Peppers, bush beans, leafy greens, and even tomatoes often make the easy to grow vegetable lists. Be sure to select vegetables that you are most likely to eat as you…
Part shade garden areas receive 4 to 6 hours of direct sunlight each day. Some annuals thrive in these conditions, and others may grow best in full sun but tolerate part shade. For these species, they may have fewer flowers or a more…
Many annual flowers perform best when they have a consistent supply of moisture throughout the growing season. However, some annuals are tolerant of dry conditions. After they’ve been planted, drought tolerant annuals may need to…
Numerous eggplant varieties (cultivars) are available for the home garden. These varieties differ in color, size, and shape. Fruit colors include green, white, pink, purple, and black. Some fruit are striped. Fruit may be…
Several varieties of grapes can be grown successfully in Iowa. The best cultivars to plant depend on where in Iowa you live, what you intend to use the grapes for (wine, fresh, etc.), and what color of fruit you want (red, white). …
Many of the best perennials for full sun are native to the prairie. Some Iowa native prairie plants that make good additions to the home landscape include:
When selecting plants for the shade garden, one group of plants that is often overlooked are native woodland wildflowers. Since they are native to the state, woodland wildflowers are well adapted to the area. They are easy to grow and…
Dozens of native prairie and woodland perennials are wonderful ornamental additions to the landscape. These plants are all native to the state of Iowa. The list includes plants that grow in a wide variety of conditions, from sun to…
