A normal adult thyroid gland weighs 10 to 20 g and receives blood from bilateral superior and inferior thyroid arteries and a small artery called the thyroid ima. The thyroid secretes two hormones. Thyroxine (T 4) makes about 90% of hormone production, and triiodothyronine (T 3) produces the other 10%.
Fast Growing Cold Hardy Tree. - Grows up to 5 ft per year! The Quaking Aspen is well known for thriving in cold climates and poor soil... but it's also a brightly colored tree with many desirable characteristics.
Fall Colors in Colorado. Aspen start turning in late August at higher elevations and the golden leaves work their way down to lower elevations in October. The peak of the fall color gold rush in this Rocky Region is usually in late September. Daylight and elevation set the timing of the color season.