Danish botanist (1835-1900).
Hjalmar Frederik Christian Kiærskou (6 August 1835 in Copenhagen – 18 March 1900), sometimes also stated as Hjalmar Kiaerskov, was a Danish botanist. Hjalmar Kiærskou was the son of landscape artist Frederik Christian Jakobsen Kiærskou (1805–1891). In 1862 he graduated as Magister for Science. In 1861 he became an assistant at the University of Copenhagen Botanical Garden. From 1875 to 1883 he was librarian at the botanical library. In 1873 he married his cousin Margrethe Olivia Gindrup. In 1883 he became an inspector at the Natural History Museum of Denmark. From 1869 to 1893 he was editor of