sinking pebbles
Hi. Some years ago, I converted a patch of moss ridden and dog fouled lawn to an area laid with 40mm red Chinese pebbles. with a path of stone flags running through it. I stripped the lawn back, and laid commercial geo-fabric on the bare soil. I then set the flag path and surrounded with 850kg of 40mm pebbles, to a depth of 75-80mm. Over the years I have replaced or added to the pebbles with a similar amount, and still need to top up. I have found the silt has risen through the geo-fabric, burying at least one layer of pebbles. I also think that the magpies and squirrels are making off with some, because in some areas, the geo-fabric is exposed. I cant stop the creatures from stealing (I don't wont to set the pebbles in concrete because it will totally spoil the present natural look), but I feel that I must tackle this in some other way. I have considered laying a sub-base on top of the fabric, and either laying self-binding gravel on that, to be topped by my pebbles, or lay the pebbles straight on the sub-base. Another alternative was to lay10-20mm gravel on the fabric with a ciovering of 40mm pebbles on top.I have also considered cutting the geo -fabric away, and digging out to give me a deeper sub-base. I cannot stop the stealing, but by using a cheaper material below, the cost of topping up will be reduced. I would be grateful for any ideas including replacing the pebbles with another material (I already have slate and tree bark in other areas of the garden). I have considered larger pebbles but the price is putting me off. Smaller pebbles, akin to gravel, will spoil the look entirely. Ideas will be gratefully received
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applestar
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Haha I don’t know anything about this, but that’s not stopping me from posting ideas. (Hey it’s part of my “charm”, ok? 
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- it seems to me you need a way to measure actual loss if only in terms of level — how about discreetly affixing anchors to permanent structures so you could run a leveling line along the top of the pebbles when filled and raked level. The line could be removed when not in use, but you could secure the line taut again when you want to see how much sinking/loss has occurred. This would also allow you to measure depth from the line to the fabric as well.
- where the fabric becomes exposed, is it loss of pebbles of is the fabric being pushed up somehow — roots, freeze/thaw action?
- do you have steep enough slope/run-off during severe storms for the pebbles to be washed downstream (are they piled up somewhere else and just need to be leveled again)?
- is it likely that wild critters could/would make off with so much? (Trying to picture a stash of the pebbles buried or in nests somewhere...) Could the loss be attributed to 2-legged kind of thieves (some people might think you could spare “a cupful”....
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...it seems like simplest way to make this as permanent as you can while maintaining the loose pebble look on the top would be to cement/concrete (as in use the pebbles in place of gravel in a concrete mix) the bottom layer in place, brushing and exposing the pebbles before the cement completely sets — I think there is a term for this technique — with raised edging along the sides of the path, then top with a layer of loose pebbles. <—- somebody else who actually knows what they are talking about could confirm whether this is a workable idea or not.
)- it seems to me you need a way to measure actual loss if only in terms of level — how about discreetly affixing anchors to permanent structures so you could run a leveling line along the top of the pebbles when filled and raked level. The line could be removed when not in use, but you could secure the line taut again when you want to see how much sinking/loss has occurred. This would also allow you to measure depth from the line to the fabric as well.
- where the fabric becomes exposed, is it loss of pebbles of is the fabric being pushed up somehow — roots, freeze/thaw action?
- do you have steep enough slope/run-off during severe storms for the pebbles to be washed downstream (are they piled up somewhere else and just need to be leveled again)?
- is it likely that wild critters could/would make off with so much? (Trying to picture a stash of the pebbles buried or in nests somewhere...) Could the loss be attributed to 2-legged kind of thieves (some people might think you could spare “a cupful”....
)...it seems like simplest way to make this as permanent as you can while maintaining the loose pebble look on the top would be to cement/concrete (as in use the pebbles in place of gravel in a concrete mix) the bottom layer in place, brushing and exposing the pebbles before the cement completely sets — I think there is a term for this technique — with raised edging along the sides of the path, then top with a layer of loose pebbles. <—- somebody else who actually knows what they are talking about could confirm whether this is a workable idea or not.
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rainbowgardener
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I was being a little dubious about the idea of squirrels taking your pebbles, so I looked it up and sure enough there are various posts about "grey squirrels" and "tree squirrels" taking rocks/pebbles/gravel from people's yards. The first couple I looked at were saying it's a mystery about what they are doing with the rocks, but this one suggests an answer:
https://thesquirrelboard.com/forums/sho ... king-Rocks
Crows and magpies are also known for taking pebbles, but anything I saw that gave any dimensions was talking about things more like 6-7 mm.
Do you walk on this area? Any gravel you walk on is likely to sink. I have put pavers down in various places in my yard. You are supposed to set them in, but sometimes I have just dropped them. After awhile they set themselves in (though not necessarily as neatly as if they had been properly laid
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https://thesquirrelboard.com/forums/sho ... king-Rocks
Crows and magpies are also known for taking pebbles, but anything I saw that gave any dimensions was talking about things more like 6-7 mm.
Do you walk on this area? Any gravel you walk on is likely to sink. I have put pavers down in various places in my yard. You are supposed to set them in, but sometimes I have just dropped them. After awhile they set themselves in (though not necessarily as neatly as if they had been properly laid
)Hi. Thank you for sharing the insight into squirrel behaviour. Several of my friends disbelieved me, but neighbours kept finding my beautiful red pebbles in their plant pots. I do not walk on the pebbles (40mm is uncomfortable), they are for decoration only, with a firmly bedded flag path running through them. I accept that the pebbles will settle but in some places the geo-fabric is exposed - hence the squirrel theory. I briefly considered setting in a cement base but laying down individual pebbles over a 6m^ is beyond boring. Mixing pebbles with cement (and then brushing out ) may be an option but I would need to get the pebble to cement ratio right to ensure that the cement bites without swallowing the pebbles. Cutting away the geo-fabric and digging down to give a firmer base is another option but I really don't see the need. As it is raining at the moment and is expected to continue until May, I have at least got time to think about it and hope that there are some ideas out there.