P.A. Mader was admitted to practice as a land surveyor in the Cape Colony in August 1858. From 1873 he collected plants in the Clanwilliam area and for some years sent specimens to P. MacOwan* at Somerset East. He also corresponded with Dr W.G. Atherstone* of Grahamstown. In 1874 Mader visited the Royal Botanic Gardens at Kew, near London, and presented them with a collection of plants from Namaqualand. Other specimens collected by him are housed in the herbarium of Albany Museum, the Bolus Herbarium at the University of Cape Town, and the Compton Herbarium in Cape Town. The species Oxalis maderi was named after him by H. Bolus*.
In the General directory... for 1886 P.A. Mader was listed as a land surveyor at Tulbach. He was probably Philippus Albertus Mader, son of Johan Adam Mader and his wife Catharina Anna Elizabeth Wege, who married Sophia Benson Earle and later Alice Hays, and had six children.