Highland Thai is an unusual variety from the highlands of northern Thailand and the nearby border regions of Burma and possibly ultimately of Chinese origin. Its appearance is quite different from the Thai-Laos gene pool of northeastern Thailand. The variety can grow exceptionally large - outdoor over 4m. It has wider leaves than other Thai Sativas. The cannabis seeds are also large, suggesting a genetic link to Yunnanese strains from China. Two main phenotypes can be formed, which is also reflected in the plant colour: green and purple. Green phenotypes often have a musky, citrus aroma.