Utah and New Mexico, as well as in the Sierra Madre Oriental Mountains and the Altiplano central highlands of Mexico. The original ancestral host of the apple maggot was the wild hawthorn (Crataegus spp.), but in the mid-1800s when the apple (Malus spp.) was introduced to North America, R. pomonella, able to take advantage of the new host, evolved. Peach, pear, cherry, plum, chokeberry, cranberry, dogwood, and fruits of the Japanese roses Rosa rugosa and Rosa carolina can also host apple maggots. However, apple maggots are not usually a serious pest of plums, cherries, and pears; larvae have been found in pears but not adult flies. Life history Flies emerge in the summer beginning in June and continuing through August and September, and eggs are laid in the apple fruit. The fly cycles through one generation a year with adults living up to four weeks. In Oregon and Washington, apple maggots have been found to emerge in early July with peak times in late August or early September. Flies have been found as late as November, and larvae have been found in late December. Females deposit eggs one by one via ovipositor in the skin of the fruit. Punctures are difficult to see with the naked eye at first but are visible once the wound darkens. A female can produce 300 to 400 eggs in her lifetime, and eggs develop in succession and are deposited as soon as they mature. Studies show that eggs develop faster at warmer temperatures that they do at cooler temperatures. When the weather is exceptionally warm, eggs may develop just two weeks after emergence. Eggs hatch within two to six days, and larvae feed on the fruit ranging from two weeks to more than two months, depending on temperature and on the hardness of the fruit. Young larvae are difficult to see because they are the same white color as the pulp. Larvae spend the pupal stage in the soil at a depth of one to two inches in the ground or sometimes in decayed fruit. Early-emerging larvae may only spend a month in the pupal stage, but late-emerging larvae remain dormant throughout the winter. Feeding behavior Haws and crab-apples are the original food source of the flies, but they have moved to feeding on mainly apples, though they have been found feeding on other cultivated fruits. Male and female flies feed constantly from the