thinking of moving soil sensors

oh about two years ago I moved my 4 soil sensors deeper into an area of the garden that had not much around it. but left the 12 and 4 inch sensor sort of out on their own… one under a group of spearment plants and the other near the raspberries. Now I am seeing that the sheltering of the ground above the sensor tends to give a different picture than what it should be in my mind.

So I acquired a drill powered auger and planning on drilling the 12 and 4 inch holes, and replanting the sensors. I did a real good initial installation, with the sensors routed through pvc pipe. So it is going to be, I am afraid, to remove the sensors in the pipe, go to the shop unthread or even cut the leads, solder , wrap the wires and replant. I did that with the 24 and 36 inch sensors, kind of put them on top of each other in the drill hole, back filled it with the soil that came out (clay) of the hole. right now I am getting pretty representative readings as the air pockets and such are gone.

With the 4 and 12 inch… I have top soil that is very dry (sitting in the garden shed for over a year now) and going to back fill with that. I am figuring that clustering the sensors around where the others are should give a better profile rather than having the spread in different zones in the garden.

The sensors will still give me the data I want and the best of all get me out of the house for at least 8 hours… if I work slow.

The ground is finally drying out after all that rain in June and May… I think summer is coming to Iowa… just intime for the fair and start of school… I am betting it will be hotter than a ducks butt in the desert.

Can’t actually determine why the soil moisture doesn’t follow the soil temperature, but it is drier at the 3 foot mark than the 2 foot, must have something to do with drainage/water movement patterns.

Just curious, will the top soil around the sensor’s possibly give a differant reading than the clay soil?

I thouhgt that too, but it has to be representative of the soil layers in that area of the garden one would have thought, and typical of the normal soil representation to give a true moisture profile. So if the rest of the soil there is top soil then that is what it should be I guess.

I clustered all my 4 soil temp/moisture sensors together and all are located under grass. It’s interesting to watch the response after rain. Over the last several rainfalls, the 4 inch soil moisture responded quickly and dropped back down to saturated as seen in the graph. Last Friday evening we had 1.82 inches in under 90 minutes and the soil moisture did not drop much at all…about 15 cb. My thinking is that it may have been due to the intensity of the rain with a lot of it running off instead of infiltrating.


SoilMoist1History.gif

well I think the sensors should be representative of the surrounding areas. the clay here is good enough to make a nifty ball,let it dry and have a fling at the neighbors cat…

By moving them I can get a better representation of what I am trying to measure their relative response. I

ah… what is interesting is the ordeal to move them… however,it will keep me out of the misses hair for a while, then I will be out of projects… :frowning:

well, that was less than a favorable outcome. I decided to move the four inch sensor. I found when I actually looked, the 4 inch temp sensor is already buried where I was going to move it, so no need.

Anyway,things went well until I began to thread the leads backward in my shop. I pulled out one lead out of the sensor. Now unless you have one of these beasts… it appears that the leads are connected to the gypsum blocks, the collar is slipped over the leads and the whole thing crimped together.

I was able to thread in my ohm meter lead into the hole and the other to the remaining sensor wire and made contact… so after a futile attempt to drop solder into the hole and push in the lead wire failed repeatedly ( ah… the plastic melted ). I came up with a temporary fix… that hasn’t been proven. I put the lead down into the hole and measured contact with the meter. then reached for my Gorrilla glue. Now that expands when it gets wet .

I figure I can do a temporary fix. that expands and holds in the probe. I drop it down into the very neatly drilled hole . cover it with dirt, hook it until the replacement sensor shows up.

I did a 2 day over night order on two sensors ( just incase I screw the pooch with the 12 inch sensor…). Oh… rain is in the forecast… just peachy…

That kind of torqued me a bit pulling that wire… I had considered pulling the block apart, but thinking the better for it… naw…

So the saga continues.

Did notice… there are some bugs living in the soil station. they come in through the wire grommet the lead wires feed into. I had thought of when all is fixed forever… to put in some silicon caulk on the place where the 8 leads come in from the bottom. Nasty creatures, they slither behind the module space between the module and case.

I also think putting some sevin powder around the base of the transmitter might wipe the buggers out when they go forage for nuts or berries or out for a night with the ladies or laddes…

I have successfully used “Plumbers Putty” to plug wire hole’s outdoor’s the keep out the critters.
It’s easy to remove years down the road if need be.

I will try that… it looks like I will be visiting the hardware store this week for some other toys.

Yup, pulling that lead out was not a stellar move on my part. I think the Gorilla glue will hold while it is in the ground… not the best repair job, but the only one I had at the moment.

Oh well… at there is a project at hand when the new sensor comes . I am kind of in the mood for a project. too bad Heath Kit isn’t still putting out those kits as they used to do. I remember I had fun in college putting in one of those short waver receivers. I remember a friend down the hall had 40 some direct shorts. we advised the physics major to learn how to solder or take up basket weaving.

I’ll pick up some of that plumbers putty, put a layer on over the bottom cable grommets . as it is, just enough space for a bug to crawl in. what is odd… I have that wireless Anenometer transmitter and no critters so far…

moved beyond the thinking stage.

I got the 4 and 12 inch soil and temperature sensors moved and planted. the moisture sensors are saturated so I am getting “o” readings for a few days.

Also found a broken wire on the 36 in sensor and that is fixed. Successfully screwed the pooch again… broke the tab off the soil temp 1 setup… it is easy to do it has a push lever and that is plastic sitting in a vice like clamp. so I had to fit the lead wire back on the rest of the clamp and use some epoxy putty to hold it. so far it is holding… the stuff sets up in 5 min.

I think I am finished out there… and out of projects… the misses is happy. :roll:

That must be a good feeling… or not! ?

Hmmm, what about the solar powered garden path light to go on the top of the mast??

Perhaps you just need to find some termites?

Preparing for another MEAD project…

What about a lightning counter from Hobby-boards? or a Boltek? Now that is real technology…

Graeme

  1. mead… I think I have all I can handle. I have 5 gallon carboy of strawberry -bananna mead aging… I am sure it will be dandy.

  2. solar light… means I will have to bring down the mast and I don’t think the wife will help on this one. her siatica seems bother her about that time.

  3. Had thought of a boltek… I could mount it on my mast… that would involve drilling a hole in the side of the brick foundation…big enough to feed out the lead, burying the cable . the attic won’t work because of the steel roof on the house… so that idea is scrapped. I did suggest to the wife to let me put in a mast, she reminded me that the gas company did bury the gas line out there and I might screw that up good.

  4. Build a computer… could do that… but school is 3 weeks away and I probably should be worrying about my integrated geometry class …

oh… I do have an additional temperature station not hooked up to anything… WD will give me readings… I just haven’t thought of what to use it for. I already have sensors in the attic, basement and lawn shed… I haven’t decided where the last sensor will go. I suppose it will come to me one day.

Water line temp?

probably cold… or hot…

the device came about as I decided I was interested in the humidity in the basement as well as temp, so I got the temp/humid sensors and put the other out of service.

I could measure the temperature in the crawl space… if all else fails.

I was interested in comparing the temp near ground surface vs ISS level for frost development. I did a test last fall using an Ibutton but a realtime sensor there would be interesting. On those clear and calm nights there can be a difference of several degrees between the air just above the ground and the air at the ISS level.

You could also make a nighttime cloud sensor (instead of a metar), by WD as a few of us have done as well! :slight_smile:

at one time I had a near ground sensor and data… last summer. I could get it refitted and installed again.

One other nice thing about WD… I can get data from WD, weatherlink only shows it on the console not anywhere else. They say that the datalogger is incapable of recording the extra data to their data base.

Made the switch… changed the station ID on the shed temp. and took the 2nd probe and using it for a soil surface temperature. Still need to take some photos for documentation, but I put it on the rear side of my soil moisture mast, down through pvc pipe, right angle bend to an piece of pvc I cut length wise (painted black) and it sits on the surface of the soil. I figure that will give me a better reading as to maximum temp. I also didn’t cement the pipe this time so I can get it apart easier if needed.
http://home.mchsi.com/~weatherdata/customscreen2.gif

That’s great - it is possible you could use that as a night-time cloud sensor as well, you just have to select it under Setup, Main Screen and Miscellaneous, it is only looked at from 5mins after sunset and up to 5 mins before sunrise when it takes over from the solar sensor, or something like that. You just have to work out the maximum temp difference below the ambient that you get. It may need a 1/2" piece of polystyrene under it to stop soil temp radiating heat into it at nighttime to allow it to get below ambient. Just watch it at nighttime to see if there is a difference. Perhaps the ambient air will keep it warm with a breeze. It’s not a perfect arrgt because of these interferences but…

Tough times ahead…
Wife is making her recipes for the fair… a Cinnamon roll in the experimental stage… either or and pecans, raisins… then we picked peaches. The danged squirrels and birds are attacking. I have live traps out there and we are getting some anyway despite the critters.

I haven’t thought of doing the cloud sensor but will give it some thought.

At just after 1am, it is showing 2deg colder than ambient ie 71deg vs 73deg and KCCI says there is a clear sky out there. If you did a trial with polystyrene underneath as a ground heat barrier, it should get colder. But that may not be what you want for a grass or surface temp sensor… Interesting. Would expect about an 8deg difference for you.