Central and North America. Species Species include: Amaranthus acanthochiton – greenstripe Amaranthus acutilobus – a synonym of Amaranthus viridis Amaranthus albus – white pigweed, tumble pigweed Amaranthus anderssonii Amaranthus arenicola – sandhill amaranth Amaranthus australis – southern amaranth Amaranthus bigelovii – Bigelow's amaranth Amaranthus blitoides – mat amaranth, prostrate amaranth, prostrate pigweed Amaranthus blitum – purple amaranth Amaranthus brownii – Brown's amaranth Amaranthus californicus – California amaranth, California pigweed Amaranthus cannabinus – tidal-marsh amaranth Amaranthus caudatus – love-lies-bleeding, pendant amaranth, tassel flower, quilete Amaranthus chihuahuensis – Chihuahuan amaranth Amaranthus crassipes – spreading amaranth Amaranthus crispus – crispleaf amaranth Amaranthus cruentus – purple amaranth, red amaranth, Mexican grain amaranth Amaranthus deflexus – large-fruit amaranth Amaranthus dubius – spleen amaranth, khada sag Amaranthus fimbriatus – fringed amaranth, fringed pigweed Amaranthus floridanus – Florida amaranth Amaranthus furcatus Amaranthus graecizans Amaranthus grandiflorus Amaranthus greggii – Gregg's amaranth Amaranthus hybridus – smooth amaranth, smooth pigweed, red amaranth Amaranthus hypochondriacus – Prince-of-Wales feather, prince's feather Amaranthus interruptus – Australian amaranth Amaranthus minimus Amaranthus mitchellii Amaranthus muricatus – African amaranth Amaranthus obcordatus – Trans-Pecos amaranth Amaranthus palmeri – Palmer's amaranth, Palmer pigweed, careless weed Amaranthus polygonoides – tropical amaranth Amaranthus powellii – green amaranth, Powell amaranth, Powell pigweed Amaranthus pringlei – Pringle's amaranth Amaranthus pumilus – seaside amaranth Amaranthus quitensis - Mucronate Amaranth Amaranthus retroflexus – red-root amaranth, redroot pigweed, common amaranth Amaranthus saradhiana Amaranthus scleranthoides – variously Amaranthus sclerantoides Amaranthus scleropoides – bone-bract amaranth Amaranthus spinosus – spiny amaranth, prickly amaranth, thorny amaranth Amaranthus standleyanus Amaranthus thunbergii – Thunberg's amaranth Amaranthus torreyi – Torrey's amaranth Amaranthus tricolor – Joseph's-coat Amaranthus tuberculatus – rough-fruit amaranth, tall waterhemp Amaranthus viridis – slender amaranth, green amaranth Amaranthus watsonii – Watson's amaranth Amaranthus wrightii – Wright's amaranth Etymology "Amaranth" derives from Greek (), "unfading", with the Greek word for "flower", (), factoring into the word's development as amaranth, the unfading flower. Amarant is an archaic variant. The name was first applied to the related Celosia (Amaranthus and Celosia share long-lasting dried flowers), as Amaranthus plants were not yet known in Europe. Ecology Amaranth weed species have an extended period of germination, rapid growth, and high rates of seed production, and have been causing problems for farmers since the mid-1990s. This is partially due to the reduction in tillage, reduction in herbicidal use and the evolution of herbicidal resistance in several species where herbicides have been applied more often. The following