Species name: Lasius niger, L. neoniger, and L. alienus
A.K.A.: Small black ants, cornfield ants, or just plain old Lasius ants
Size: 0.12-0.2 inches
Where it lives: Lasius ants prefer open spaces, and will set up their anthills in grassy areas like golf courses or traffic medians, but sometimes nest under stones or in logs.
What it eats: Aphid experts, Lasius ants tend aphids like cattle milking them for honeydew and sometimes killing them for a big aphid steak.
What’s the big deal?
Before I met my husband, an electrical engineer, the only thing I knew for sure that engineers did was drive trains. Sure, I knew tons of people who said they were engineers of one kind or another, but once I found out they weren’t wearing cool hats conducting thousands of tons of steel hurtling at lightning speeds down railroad tracks, my brain would glaze over and I’d lose interest in their profession.
“You mean you have no giant horn to blare at passersby as you cross over city streets and along the countryside? BO-ring!” I used to think.
Then I met the man who would become my husband. As he talked about his job, I learned that many different kinds of engineers work to keep our world safe and running smoothly. Civil engineers, for example, prevent tragedy by designing safe roads, buildings, and bridges. Electrical engineers plan the circulatory system of wires and currents coursing through our cities. Aerospace engineers launch us into the sky and even outer space. Many more types of engineers tool away behind the scenes, perfecting our lives without our noticing.
In nature, some ant species work as engineers, shaping and refining the environment, building connections, repairing bonds. Lasius ants are one group renowned for being superior soil engineers. A little larger than a sesame seed, Lasius (Lay-see-us) look more like regular ole ants than the movers and the shakers of nature. They resemble odorous house ants with slightly larger (and fuzzier) behinds, and are generally darkish brown to deep brownish-black in color. While odorous house ants move like troopers marching in line to and from their favorite foods, Lasius ants move more like my favorite Aunt Ann: deftly, but with a bit of a waddle, probably owing a bit to those fuller fannies.
Three Lasius species make the most common list: the small black ant (Lasius niger), the cornfield ant (Lasius neoniger), and Lasius alienus (no common name yet). All Lasius species have only one queen per colony and prefer to nest in soil in open areas or under logs and stones. Oftentimes, their nests look like little volcanoes popping up across grassy areas, and, since one nest can have many entrances, they can look like an erupting mountain range spreading out across the landscape.
Lasius ants are often the most abundant ant species on golf courses, happily setting up shop in the expansive open habitat that seems tailor-made just for them. These ants’ abodes get them into trouble with golfers, who would prefer their putting greens smooth and free of ant-made speed bumps. But researchers studying Lasius show that when exterminators try to smooth the greens by poisoning Lasius ants, more destructive golf course pests like Japanese beetle larvae and cutworms thrive.
In addition to the rolling green, Lasius ants love golf courses because they love sugar. Yes, these pristine courses may be free of half-eaten Snickers bars—but Lasius ants have their eyes on a different type of sugary treat: chubby, sugar-making insects called root aphids who slurp away at underground grass roots. Lasius ants show off their extra-engineering talents as farmers and ranchers by protecting these root aphids from predators with little mouth-built sheds, all the while milking them for their sugar.
Lasius ants are “aphid experts.” They can climb up a tree and tell which aphids like ants and which don’t just by sniffing with their antennae. No dummies when it comes to sugar, they prefer the sweetest sugar around. They’ll walk around trees sniffing aphid butts until they find the species that produces the sweetest sugar. Whoever wins the sweetest award gets protected and tended by the ants. They’re so good at kicking out predators that a ladybug will avoid laying eggs in any area where she even catches a whiff of Lasius ants.
Just as some farmers need to kill part of their cow herd to eat meat, Lasius ants need to kill some of their aphid herd for protein. How can you choose your best beef from all of your best-producing Bessies? If you’re a Lasius ant, you follow your nose. Lasius ants eat aphids from their herd that they or their sisters haven’t tended. They can tell who’s been milked by sniffing the aphids to see if they’ve been touched by a member of the colony.
But enough about sugar. Back to the engineering. Lasius ants engineer soil. To understand how they help develop our dirt, we first need to understand a little bit more about the good ole terra firma, which props us up right this second, whether we think about it or not. Even though dirt might seem as dead as dead gets, healthy soil actually lives and breathes just like we do. As dead plants and animals decompose, altering nutrients and gasses, microorganisms scoot around gobbling up some nutrients and turning them into other nutrients. Animals like earthworms push the dirt about, letting air flow through, speeding up biological processes that increase life-promoting properties within the soil. When nobody contributes to these processes, plants and animals can’t survive because the soil gets compacted and hard, with nutrients concentrated in some places and not others.
Lasius ants are among the first species to pop their tents in disturbed areas, and from the moment they move in, they start turning the soil and making the ground ready for life. They burrow their tunnels into the soil, tripling soil respiration, the soil’s ability to “breathe,” compared to non-Lasius areas. They do such a good job at aeration that more insects and spiders move into those Lasius-affected, loosely-compacted, fresh-air areas, which has a cascade of positive effects on the ecosystem around them. They carry dead insects and sweet treats from one place to another, spreading out some soil nutrients and concentrating others, which increase all kinds of chemical and biological processes. They even help fix nitrogen, an important chemical for healthy plant growth. Just like the engineers who press our world and help it flow, Lasius ants churn and build wherever they live.
When was the last time you rode over a bridge or walked into a building and thought, “Gosh, isn’t it nice? I’m not afraid this building/bridge will collapse on me”? Probably never. We don’t think about it because we don’t have to. Thanks to our engineers, things work.
The same goes for soil in our natural areas. We seem to only pay attention to our soil when it stops working well, plants die, animals move out and the soil actually becomes stone dead. Our Lasius engineers, like my husband and the engineers that reinforce and shape our human-made world, don’t seem to mind that we don’t notice. They don’t need us to shower them with thanks, but they do need us to give them the space and resources they need to do their best work. Keep your eyes peeled for volcanoes on the putting green or in your city’s medians. See if you can spot a sesame seed waddling out. Give it a salute as it passes by, conducting its business of building and bettering our world.
Cammeraat, E. L. H. & Risch, A. C. 2008. The impact of ants on mineral soil properties and processes at different spatial scales. Journal of Applied Entomology, 132, 285-294. doi: 10.1111/j.1439-0418.2008.01281.x.
Czechowski, W., Vepsalainen, K. & Radchenko, A. 2013. Ants on skerries: Lasius assemblages along primary succession. Insectes Sociaux, 60, 147-153. doi: 10.1007/s00040-012-0278-y.
Dauber, J. & Wolters, V. 2004. Edge effects on ant community structure and species richness in an agricultural landscape. Biodiversity and Conservation, 13, 901-915. doi: 10.1023/B:BIOC.0000014460.65462.2b.
Dussutour, A. & Simpson, S. J. 2012. Ant workers die young and colonies collapse when fed a high-protein diet. Proceedings of the Royal Society B-Biological Sciences, 279, 2402-2408. doi: 10.1098/rspb.2012.0051.
FIEDLER, K. & SAAM, C. 1995. Ants Benefit from Attending Facultatively Myrmecophilous Lycaenidae Caterpillars - Evidence from a Survival Study. Oecologia, 104, 316-322. doi: 10.1007/BF00328367.
Golichenkov, M. V., Neimatov, A. L. & Kiryushin, A. V. 2009. Microbiological activity of soils populated by Lasius niger ants. Eurasian Soil Science, 42, 788-792. doi: 10.1134/S1064229309070096.
Grueter, C., Czaczkes, T. J. & Ratnieks, F. L. W. 2011. Decision making in ant foragers (Lasius niger) facing conflicting private and social information. Behavioral Ecology and Sociobiology, 65, 141-148. doi: 10.1007/s00265-010-1020-2.
Grzes, I. M. 2009. Cadmium regulation by Lasius niger: A contribution to understanding high metal levels in ants. Insect Science, 16, 89-92. doi: 10.1111/j.1744-7917.2009.00258.x.
Holec, M. & Frouz, J. 2006. The effect of two ant species Lasius niger and Lasius flavus on soil properties in two contrasting habitats. European Journal of Soil Biology, 42, S213-S217. doi: 10.1016/j.ejsobi.2006.07.033.
Itioka, T. & Inoue, T. 1996. The consequences of ant-attendance to the biological control of the red wax scale insect Ceroplastes rubens by Anicetus beneficus. Journal of Applied Ecology, 33, 609-618. doi: 10.2307/2404989.
JORDANO, D. & THOMAS, C. 1992. Specificity of an Ant-Lycaenid Interaction. Oecologia, 91, 431-438. doi: 10.1007/BF00317634.
Kaneko, S. 2003. Different impacts of two species of aphid-attending ants with different aggressiveness on the number of emerging adults of the aphid's primary parasitoid and hyperparasitoids. Ecological Research, 18, 199-212. doi: 10.1046/j.1440-1703.2003.00547.x.
Katayama, N. & Suzuki, N. 2003. Bodyguard effects for aphids of Aphis craccivora Koch (Homoptera : Aphididae) as related to the activity of two ant species, Tetramorium caespitum Linnaeus (Hymenoptera : Formicidae) and Lasius niger L. (Hymenoptera : Formicidae). Applied Entomology and Zoology, 38, 427-433. doi: 10.1303/aez.2003.427.
Lang, C. & Menzel, F. 2011. Lasius niger ants discriminate aphids based on their cuticular hydrocarbons. Animal Behaviour, 82, 1245-1254. doi: 10.1016/j.anbehav.2011.08.020.
Lopez, R. & Potter, D. 2003. Biodiversity of ants (Hymenoptera : Formicidae) in golf course and lawn turf habitats in Kentucky. Sociobiology, 42, 701-713.
Lopez, R. & Potter, D. 2000. Ant predation on eggs and larvae of the black cutworm (Lepidoptera : Noctuidae) and Japanese beetle (Coleoptera : Scarabaeidae) in turfgrass. Environmental Entomology, 29, 116-125. doi: 10.1603/0046-225X-29.1.116.
Maier, R. & Potter, D. 2005. Factors affecting distribution of the mound-building ant Lasius neoniger (Hymenoptera : Formicidae) and implications for management on golf course putting greens. Journal of economic entomology, 98, 891-898.
Mailleux, A., Deneubourg, J. & Detrain, C. 2009. Food transport in ants: Do Lasius niger foragers maximize their individual load? Comptes Rendus Biologies, 332, 500-506. doi: 10.1016/j.crvi.2008.10.005.
Nagy, C., Cross, J. V. & Marko, V. 2013. Sugar feeding of the common black ant, Lasius niger (L.), as a possible indirect method for reducing aphid populations on apple by disturbing ant-aphid mutualism. Biological Control, 65, 24-36. doi: 10.1016/j.biocontrol.2013.01.005.
Offenberg, J. 2001. Balancing between mutualism and exploitation: the symbiotic interaction between Lasius ants and aphids. Behavioral Ecology and Sociobiology, 49, 304-310. doi: 10.1007/s002650000303.
Oliver, T. H., Jones, I., Cook, J. M. & Leather, S. R. 2008. Avoidance responses of an aphidophagous ladybird, Adalia bipunctata, to aphid-tending ants. Ecological Entomology, 33, 523-528. doi: 10.1111/j.1365-2311.2008.01009.x.
SAKATA, H. 1994. How an Ant Decides to Prey on Or to Attend Aphids. Researches on Population Ecology, 36, 45-51. doi: 10.1007/BF02515084.
Sakiyama, T. & Gunji, Y. P. 2013. Garden ant homing behavior in a maze task based on local visual cues. Insectes Sociaux, 60, 155-162. doi: 10.1007/s00040-012-0279-x.
Schuch, S., Platner, C. & Sanders, D. 2008. Potential positive effect of the ant species Lasius niger on linyphiid spiders. Journal of Applied Entomology, 132, 375-381. doi: 10.1111/j.1439-0418.2008.01287.x.
Schwartzberg, E. G., Johnson, D. W. & Brown, G. C. 2010. The Influence of Lasius neoniger (Hymenoptera: Formicidae) on Population Growth and Biomass of Aphis glycines (Hemiptera: Aphididae) in Soybeans. Environmental Entomology, 39, 1788-1793. doi: 10.1603/EN10120.
tewart-Jones, A., Pope, T. W., Fitzgerald, J. D. & Poppy, G. M. 2008. The effect of ant attendance on the success of rosy apple aphid populations, natural enemy abundance and apple damage in orchards. Agricultural and Forest Entomology, 10, 37-43. doi: 10.1111/j.1461-9563.2007.00353.x.
Tegelaar, K., Hagman, M., Glinwood, R., Pettersson, J. & Leimar, O. 2012. Ant-aphid mutualism: the influence of ants on the aphid summer cycle. Oikos, 121, 61-66. doi: 10.1111/j.1600-0706.2011.19387.x.
Torgersen, T. & Bull, E. 1995. Down logs as habitat for forest-dwelling ants - The primary prey of pileated woodpeckers in northeastern Oregon. Northwest Science, 69, 294-303.
Verheggen, F. J., Diez, L., Sablon, L., Fischer, C., Bartram, S., Haubruge, E. & Detrain, C. 2012. Aphid Alarm Pheromone as a Cue for Ants to Locate Aphid Partners. Plos One, 7, e41841. doi: 10.1371/journal.pone.0041841.
Volkl, W., Woodring, J., Fischer, M., Lorenz, M. & Hoffmann, K. 1999. Ant-aphid mutualisms: the impact of honeydew production and honeydew sugar composition on ant preferences. Oecologia, 118, 483-491. doi: 10.1007/s004420050751.
Warren,Robert J.,,II, Giladi, I. & Bradford, M. A. 2012. Environmental Heterogeneity and Interspecific Interactions Influence Nest Occupancy By Key Seed-Dispersing Ants. Environmental Entomology, 41, 463-468. doi: 10.1603/EN12027.
Wu, H., Batzer, D. P., Yan, X., Lu, X. & Wu, D. 2013a. Contributions of ant mounds to soil carbon and nitrogen pools in a marsh wetland of Northeastern China. Applied Soil Ecology, 70, 9-15. doi: 10.1016/j.apsoil.2013.04.004.
Wu, H., Lu, X., Wu, D., Song, L., Yan, X. & Liu, J. 2013b. Ant mounds alter spatial and temporal patterns of CO2, CH4 and N2O emissions from a marsh soil. Soil Biology & Biochemistry, 57, 884-891. doi: 10.1016/j.soilbio.2012.10.034.