Rare mushrooms are the strangest item in the ARK resource set. They weigh 0.2, stack to 100, give 25 food, and take 259,200 seconds — three days — to spoil. In a game where organic polymer dies in thirty minutes and cactus sap in ten, a perishable with a 72-hour shelf life is effectively a non-perishable.
The numbers also make rare mushrooms a legitimate emergency food, which is not how most players think of them. Both readings are supported by the cached data in ark-resources.json and ark-items.json.
The rare mushroom card
| Property | Value |
|---|---|
| Weight | 0.2 |
| Stack size | 100 |
| Weight per full stack | 20 |
| Food | 25 |
| Spoils in | 259,200 seconds (72 hours) |
| Decomposes in | 120 seconds |
| Hexagon value | 120 |
| Exchange quantity | 5 |
| Mobile purchase | 100 mixes |
| Renewable | Yes |
Rare mushrooms are a forage resource that leaves you lightheaded when handled. — ARK Wiki
The flavour text is doing double duty: it explains why the item looks like a hazard and why it is classed as a fungus rather than a plant. Mechanically, it is a food item with a crafting-grade hexagon value.
72 hours is the headline number
Line the perishables up and the design intent is obvious:
| Item | Spoil time | Stack | Notes |
|---|---|---|---|
| Rare Mushroom | 259,200 s (72 h) | 100 | Food 25 |
| Organic Polymer | 1,800 s (30 min) | 20 | Also -500 health |
| Cooked Meat | 1,200 s (20 min) | 50 | Food 20 |
| Cactus Sap | 600 s (10 min) | 100 | Food 1 |
| Unstable Element Shard | 30 s | not listed | Extinction only |
Rare mushrooms outlast cooked meat by a factor of 216. They outlast organic polymer by 144. Whatever else you say about a swamp trip, the cargo does not rot while you are flying home — which is more than can be said for half the mid-game materials.
That has a direct planning consequence: rare mushrooms are one of the few perishables you can bank. A chest of 300 mushrooms is 60 weight and three days of shelf life, so a stock built on Monday still exists on Wednesday. The resources strategy page treats stable perishables differently from volatile ones for exactly this reason.
Food per slot: 2,500 in one square
The food value is the part almost everyone ignores. Twenty-five food per unit, 100 per stack:
| Item | Food per unit | Stack | Food per full stack |
|---|---|---|---|
| Rare Mushroom | 25 | 100 | 2,500 |
| Cooked Meat | 20 | 50 | 1,000 |
| Amarberry | 1.5 | 100 | 150 |
| Azulberry | 1.5 | 100 | 150 |
One stack of rare mushrooms is 2,500 food, which is more than two and a half stacks of cooked meat and more than sixteen stacks of berries — in a single slot. For a player stranded without a preserving bin, or running a long scouting trip where slots matter more than weight, that is a real provisioning option.
The trade-off is weight: 20 per stack versus 5 for cooked meat (0.1 x 50) and roughly 5 for a berry stack. Rare mushrooms are 4x heavier per food unit than cooked meat, so they are a slot solution rather than a weight solution. The survival guide covers the food maths for long trips in more detail.
The 120-second decomposition timer
The infobox separates two timers that players usually conflate. Spoil time is how long the item lasts in an inventory. Decomposition time is how long it takes to vanish once it is on the ground — 120 seconds for a rare mushroom.
That second number is the one that costs you a harvest. If you are chopping mangroves and your inventory fills, the mushrooms that drop are gone in two minutes, not three days. The shelf life only applies to what you actually pick up.
Two habits follow. First, clear inventory space before a swamp run rather than during it. Second, do not drop a partial stack to make room for something else — you are trading a 72-hour item for a 2-minute floor decoration.
Where they come from
The dataset lists rare mushrooms as renewable and assigns them a hexagon value of 120, but it does not publish a drop table, so the sourcing advice has to stay structural. The three routes that matter in practice are the swamp mangroves, giant beaver dams, and crystal nodes — the first two deliver them in bulk, the third as a by-product of a run you were making anyway.
The by-product route is the efficient one. Crystal is needed for the Fabricator (15), the Chemistry Bench (250) and the Industrial Forge (250), so any crystal trip can carry mushrooms home for free. The crystal page covers those nodes.
For deliberate farming, the swamp is the destination: the Therizinosaurus converts a mangrove stand into a stack in a couple of minutes, and the best gatherers guide page lists the plant specialists.
Hexagons, mobile prices and the trading floor
At 120 hexagons per unit with an exchange quantity of 5, rare mushrooms sit in the same band as crystal (115) and silica pearls (125). That is a higher valuation than wood (25) or stone (40) despite mushrooms being a food item, and it is consistent with the “useful in crafting” framing of the infobox.
On mobile, the purchase price is 100 mixes, which puts them alongside other Chef Station stock. None of this changes a PC run, but it confirms the item is treated as a utility input rather than a snack.
Should you farm them at all?
The honest answer from the data: farm them when you are already in the swamp or already mining crystal, and do not build a base around them. Their value is stability and food density, not scarcity — the stack is generous, the spoil timer is irrelevant, and nothing in the structure recipes depends on them.
Where they earn a slot is on long expeditions and in early bases without refrigeration: 20 weight for 2,500 food is a good trade when you cannot afford a preserving bin yet. The beginner guide covers the point in progression where that stops being true.