We don’t sell aluminum tags. There are jobs where they’re the better buy, and this is how to tell whether you’ve got one. For the wider picture, including plastic, see plastic, aluminum or stainless steel.
Aluminum is the right choice for some jobs
It doesn’t rust. It grows its own oxide skin, which is why a tag nailed to a trunk in 1998 is still readable. It’s soft enough to emboss with a hand tool, so you can number four hundred trees in the field without a machine. And it’s cheap, often under a dollar a tag in quantity.
If what you need is a number that points at a row in a spreadsheet, buy aluminum. Stainless is an expensive way to write “247”.
Two things kill an aluminum tag
The first is the softness that made it easy to emboss in the first place. A branch, a hailstone or a string trimmer flattens the digits back out, and embossed text shallows a little more every year it rubs.
The second is chemistry. Aluminum doesn’t like alkalinity and chloride together, and that’s a description of an orchard: fertilizer salts, irrigation water, coastal air if you’re near the coast. It pits. Hang it on a galvanized nail and it goes faster, because in a galvanic pair aluminum is the one that gives.
What 316L buys you
Molybdenum, mostly. It’s the marine grade, roughly a third more pitting resistance than ordinary 304, and the reason it ends up on boat fittings. The full specification is here.
The bigger difference isn’t the metal, it’s the text. Embossing pushes a shape into the surface. Laser ablation takes metal out. There’s nothing left to flatten.
Which one you should buy
| You are | Buy |
|---|---|
| Numbering trees for a survey or inventory | Aluminum |
| Tagging a research plot on a budget | Aluminum |
| Naming a tree you’ll still own in twenty years | 316L stainless |
| Labeling an orchard on a coastal or high-fertilizer site | 316L stainless |
| Running a nursery where the customer reads the tag | 316L stainless |
Short version: if the tag holds a number, buy aluminum. If it holds the only record of what the tree is, it has to outlive the tree, and that’s a different piece of metal. Ours are engraved 316L stainless tree tags, made one at a time with your own text.