What are the squat metal cylinders I see sitting on range-land fence posts?

September 4, 2008 5:12 PM

What are the (sensors, recorders?) things that look like metal cake covers (short, wide cylinders) sitting on fence-posts, mostly in rangeland in the Western USA?

I've only seen them on fence lines along roads, and they tend to sit on little shelves on the posts. They're usually almost as wide as they are tall, but sometimes taller than they are wide, and tend to be painted light green or grey, but I've seen them in stainless steel. They are always cylindrical.

They don't have a visible power source.

I don't think I've seen them east of the Rockies, but I'm not ready to swear to that.

Seismaphones? Something else? I'd love to know!

posted by dolface to science & nature (9 comments total)

Boll Weevil trap? Or the things that are much bigger? Boll Weevil traps are about the size of a two-litre coke bottle.
posted by tayknight at 6:04 PM on September 4, 2008

Anything like this?
posted by tomierna at 6:15 PM on September 4, 2008

Power supplies for electric fences?
posted by sebastienbailard at 6:58 PM on September 4, 2008

My first guess is the same as tayknight's: some kind of insect collector/trap.

Could the possibly be bird houses?

I really doubt they are seismometers since a good stiff wind can move the fence enough to shake the post considerably.

Are they featureless? Any chance of solar cells on the top?
posted by Ookseer at 7:18 PM on September 4, 2008

They're fairly common in rural areas of SoCal mountains and deserts, though the ones I've seen are always mounted on utility poles and have stainless steel housings. I'm glad someone asked becuase I see them frequently and am also curious.
posted by buggzzee23 at 7:34 PM on September 4, 2008

Definitely T1 repeaters. They're everywhere, if you know what to look for. There's a ton of phone equipment like this scattered about the country that most people generally don't notice. It's just more obvious in rural areas.

To clarify, I'm guessing the original poster meant a "fence pole", but not necessarily one that's part of a fence. At least that's where T1 repeaters are. I could be wrong about the poster's intent though.

Now that I think about it though, I really can't tell you where the power comes from.
posted by kiltedtaco at 7:55 PM on September 4, 2008

They are meteorological sensors/data loggers that are most commonly used for temperature and humidity monitoring.

They are battery powered and wireless. The newer models have a radiation shield as visible in the link above, the older ones have radiation shields that look like stainless steel or aluminum cake covers.

I guarantee that there are more of these to be found east of the Rockies than west of that range...
posted by cinemafiend at 8:44 PM on September 4, 2008

I should clarify: the exact device that you have described is definitely a meteorological data logger that ranchers, farmers, and employees of the Department of Agriculture like to mount to fence posts.

kiltedtaco has decribed a similar looking device that are found on telephone poles or on small posts along buried fiber-optic cables.

I would suggest taking a look at the book A FIELD GUIDE TO ROADSIDE TECHNOLOGY. By no means an exhaustive work, it will definitely open you eyes to some of the most common technologies to be found along American roads in the 21st century.
posted by cinemafiend at 9:07 PM on September 4, 2008

kiltedtaco nailed it, and thanks to tomierna for the link to the pic!
posted by dolface at 8:55 AM on September 5, 2008