Weed, insect, and disease control may also be required for pastures. A healthy, productive pasture will resist invasion from most poisonous weeds and provide good quality forage. When pastures are overgrazed, horses will eat the grass and legume species down to the soil, which allows weeds to take over.
1 Melasma can be triggered by birth control pills because it increases hormones throughout the body. # 2  This is one of the most common causes of melasma. 3  Pregnancy: During pregnancy the body will become very hormonal and skin conditions like acne vulgaris and melasma/chloasma become very common.
Melasma, also known as chloasma and the mask of pregnancy, is a common skin condition that usually develops in women between 20 and 50 years old. It is believed to be caused by excessive sun exposure as well as hormonal events such as pregnancy, taking oral contraceptives, and hormone replacement therapy.