The cattle
fever tick, Rhipicephalus (Boophilus) microplus, is the most economically important tick worldwide. Infestations with this tick can lead to direct damage and cattle mortality due to the transmission of potentially deadly pathogens. Management of this tick species has been focused on the use of synthetical
acaricides; however, the emergence of
acaricide resistance to single or multiple active ingredients has resulted in a need for novel
acaricide compounds. Among potential avenues for the discovery of novel
acaricides are
plant-derived compounds. The efficacy of five organic compounds (
nootkatone, Stop the Bites®, BioUD®,
lavender oil, and
cedarwood oil) was evaluated using larval immersion tests (LITs), repellency assays, and adult immersion tests (AITs). The results from the LITs indicate that three of the organic compounds (NootkaShield™, Stop the
Bites,
BioUD) led to significant mortalities at low concentrations (0.2, 0.02, and 0.08%, respectively). By comparison, lavender and
cedar oil led to around 90% mortality
at 10 and 1% concentrations, respectively. Similarly, NootkaShield, Stop the
Bites, and
BioUD had strong repellent properties with over 90% repellency at the two highest concentrations tested. Using the FAO 2004 guidelines, we evaluated the effectiveness of these organic compounds at reducing the fecundity of R. (B.) microplus and show that
Nootkatone, Stop the
Bites, and
BioUD may significantly decrease tick populations (Drummond's index > 90% at concentrations of 5%), highlighting their potential as alternatives to synthetic
acaricides for the control of cattle
fever ticks.