FungRadar

Foraging forecast: Istarska

Yes — conditions in Istarska in September 2026 are good, index 66 out of 100, with penny bun furthest along. That is a reading of weather, woodland and season: it does not promise you a full basket, but this is one of the weeks worth going out.

A seven-day index for the species whose records are confirmed here — 25 of them right now. Flush phases and the factors behind the number, instead of a "chance of finding" percentage we cannot measure. Data updated 17 September 2026, 11:22 BST.

The map is built from the measurement network — one point per sizeable town and more in between. A detailed 2.5 km grid is computed for one region so far: it needs its own run for every cell.

Best today

Penny Bun

Boletus edulis

Buildingconfidence 47%

Flush phase

  1. Quiet
  2. Starting
  3. Building
  4. Peak
  5. Fading

Updated 17 September 2026, 11:22 BST

Map

Where to look: Istarska

Values are computed at measurement points and interpolated between them. Clicking a point opens that town.

Open the interactive map

By species

The week, species by species

Each row is its own seven days. Today is outlined.

Penny Bun — botanical illustration

Penny Bun

Boletus edulis

Building66 today

Week's best 72 — on Sundayaverage 70by the weekend steady

Conditions are best on Sunday.

  1. Today6617 Sept
  2. Fri6918 Sept
  3. Sat7019 Sept
  4. Sun7220 Sept
  5. Mon7221 Sept
  6. Tue7222 Sept
  7. Wed7023 Sept
Honey Fungus — botanical illustration

Honey Fungus

Armillaria mellea

Starting44 today

Week's best 51 — on Tuesdayaverage 48by the weekend rising

Conditions are best on Tuesday.

  1. Today4417 Sept
  2. Fri4418 Sept
  3. Sat4619 Sept
  4. Sun4820 Sept
  5. Mon5021 Sept
  6. Tue5122 Sept
  7. Wed5123 Sept
Weeping Bolete — botanical illustration

Weeping Bolete

Suillus granulatus

Building56 today

Week's best 64 — on Tuesdayaverage 60by the weekend rising

Conditions are best on Tuesday.

  1. Today5617 Sept
  2. Fri5418 Sept
  3. Sat5619 Sept
  4. Sun6020 Sept
  5. Mon6321 Sept
  6. Tue6422 Sept
  7. Wed6423 Sept
Oyster Mushroom — botanical illustration

Oyster Mushroom

Pleurotus ostreatus

Quiet0 today

Week's best 0average 0by the weekend steady

Conditions stay poor all week — not worth the trip yet.

  1. Today017 Sept
  2. Fri018 Sept
  3. Sat019 Sept
  4. Sun020 Sept
  5. Mon021 Sept
  6. Tue022 Sept
  7. Wed023 Sept
Velvet Shank — botanical illustration

Velvet Shank

Flammulina velutipes

Quiet0 today

Week's best 0average 0by the weekend steady

Conditions stay poor all week — not worth the trip yet.

  1. Today017 Sept
  2. Fri018 Sept
  3. Sat019 Sept
  4. Sun020 Sept
  5. Mon021 Sept
  6. Tue022 Sept
  7. Wed023 Sept
Brown Birch Bolete — botanical illustration

Brown Birch Bolete

Leccinum scabrum

Starting54 today

Week's best 60 — on Mondayaverage 57by the weekend rising

Conditions are best on Monday.

  1. Today5417 Sept
  2. Fri5418 Sept
  3. Sat5519 Sept
  4. Sun5820 Sept
  5. Mon6021 Sept
  6. Tue6022 Sept
  7. Wed6023 Sept
Orange Oak Bolete — botanical illustration

Orange Oak Bolete

Leccinum aurantiacum

Building58 today

Week's best 65 — on Tuesdayaverage 62by the weekend rising

Conditions are best on Tuesday.

  1. Today5817 Sept
  2. Fri6018 Sept
  3. Sat6219 Sept
  4. Sun6320 Sept
  5. Mon6421 Sept
  6. Tue6522 Sept
  7. Wed6423 Sept
Chanterelle — botanical illustration

Chanterelle

Cantharellus cibarius

Building55 today

Week's best 59average 58by the weekend steady

The week is flat — no day to pick, conditions are the same throughout.

  1. Today5517 Sept
  2. Fri5718 Sept
  3. Sat5819 Sept
  4. Sun5820 Sept
  5. Mon5921 Sept
  6. Tue5922 Sept
  7. Wed5823 Sept
Lactarius resimus — botanical illustration

Lactarius resimus

Lactarius resimus

Starting46 today

Week's best 50average 49by the weekend steady

The week is flat — no day to pick, conditions are the same throughout.

  1. Today4617 Sept
  2. Fri4818 Sept
  3. Sat4919 Sept
  4. Sun5020 Sept
  5. Mon5021 Sept
  6. Tue5022 Sept
  7. Wed4923 Sept
Saffron Milkcap — botanical illustration

Saffron Milkcap

Lactarius deliciosus

Starting48 today

Week's best 53 — on Mondayaverage 51by the weekend steady

Conditions are best on Monday.

  1. Today4817 Sept
  2. Fri5018 Sept
  3. Sat5119 Sept
  4. Sun5220 Sept
  5. Mon5321 Sept
  6. Tue5322 Sept
  7. Wed5223 Sept
Bay Bolete — botanical illustration

Bay Bolete

Imleria badia

Building59 today

Week's best 66 — on Tuesdayaverage 63by the weekend rising

Conditions are best on Tuesday.

  1. Today5917 Sept
  2. Fri6218 Sept
  3. Sat6419 Sept
  4. Sun6420 Sept
  5. Mon6521 Sept
  6. Tue6622 Sept
  7. Wed6423 Sept
Sheathed Woodtuft — botanical illustration

Sheathed Woodtuft

Kuehneromyces mutabilis

Building54 today

Week's best 59 — on Mondayaverage 55by the weekend steady

Conditions are best on Monday.

  1. Today5417 Sept
  2. Fri5118 Sept
  3. Sat5319 Sept
  4. Sun5620 Sept
  5. Mon5921 Sept
  6. Tue5822 Sept
  7. Wed5723 Sept
Field Blewit — botanical illustration

Field Blewit

Collybia personata

Starting36 today

Week's best 42 — on Tuesdayaverage 38by the weekend steady

Conditions are poor: even the week's best day only reaches «slow».

  1. Today3617 Sept
  2. Fri3418 Sept
  3. Sat3519 Sept
  4. Sun3820 Sept
  5. Mon4121 Sept
  6. Tue4222 Sept
  7. Wed4023 Sept
Wood Blewit — botanical illustration

Wood Blewit

Collybia nuda

Starting38 today

Week's best 44 — on Mondayaverage 41by the weekend rising

Conditions are poor: even the week's best day only reaches «slow».

  1. Today3817 Sept
  2. Fri3618 Sept
  3. Sat3819 Sept
  4. Sun4220 Sept
  5. Mon4421 Sept
  6. Tue4422 Sept
  7. Wed4423 Sept
Field Mushroom — botanical illustration

Field Mushroom

Agaricus campestris

Building57 today

Week's best 61 — on Tuesdayaverage 58by the weekend steady

Conditions are best on Tuesday.

  1. Today5717 Sept
  2. Fri5318 Sept
  3. Sat5519 Sept
  4. Sun5820 Sept
  5. Mon6021 Sept
  6. Tue6122 Sept
  7. Wed6123 Sept
Fairy Ring Champignon — botanical illustration

Fairy Ring Champignon

Marasmius oreades

Building55 today

Week's best 58 — on Wednesdayaverage 55by the weekend steady

Conditions are best on Wednesday.

  1. Today5517 Sept
  2. Fri5018 Sept
  3. Sat5219 Sept
  4. Sun5420 Sept
  5. Mon5621 Sept
  6. Tue5722 Sept
  7. Wed5823 Sept
Parasol — botanical illustration

Parasol

Macrolepiota procera

Building62 today

Week's best 66 — on Mondayaverage 63by the weekend steady

Conditions are best on Monday.

  1. Today6217 Sept
  2. Fri5918 Sept
  3. Sat6019 Sept
  4. Sun6420 Sept
  5. Mon6621 Sept
  6. Tue6622 Sept
  7. Wed6523 Sept
Common Puffball — botanical illustration

Common Puffball

Lycoperdon perlatum

Building55 today

Week's best 58 — on Tuesdayaverage 55by the weekend steady

Conditions are best on Tuesday.

  1. Today5517 Sept
  2. Fri5018 Sept
  3. Sat5219 Sept
  4. Sun5520 Sept
  5. Mon5721 Sept
  6. Tue5822 Sept
  7. Wed5823 Sept
Red Cracking Bolete — botanical illustration

Red Cracking Bolete

Xerocomellus chrysenteron

Building58 today

Week's best 64 — on Mondayaverage 62by the weekend steady

Conditions are best on Monday.

  1. Today5817 Sept
  2. Fri6018 Sept
  3. Sat6119 Sept
  4. Sun6220 Sept
  5. Mon6421 Sept
  6. Tue6422 Sept
  7. Wed6223 Sept
Bovine Bolete — botanical illustration

Bovine Bolete

Suillus bovinus

Starting50 today

Week's best 56 — on Mondayaverage 54by the weekend rising

Conditions are best on Monday.

  1. Today5017 Sept
  2. Fri5218 Sept
  3. Sat5319 Sept
  4. Sun5520 Sept
  5. Mon5621 Sept
  6. Tue5622 Sept
  7. Wed5523 Sept
Milk White Brittlegill — botanical illustration

Milk White Brittlegill

Russula delica

Building54 today

Week's best 61 — on Mondayaverage 59by the weekend rising

Conditions are best on Monday.

  1. Today5417 Sept
  2. Fri5718 Sept
  3. Sat5819 Sept
  4. Sun6020 Sept
  5. Mon6121 Sept
  6. Tue6122 Sept
  7. Wed6023 Sept
Black Morel — botanical illustration

Black Morel

Morchella elata

Quiet0 today

Week's best 0average 0by the weekend steady

Conditions stay poor all week — not worth the trip yet.

  1. Today017 Sept
  2. Fri018 Sept
  3. Sat019 Sept
  4. Sun020 Sept
  5. Mon021 Sept
  6. Tue022 Sept
  7. Wed023 Sept
Fly Agaric — botanical illustration

Fly Agaric

Amanita muscaria

Starting52 today

Week's best 58 — on Tuesdayaverage 55by the weekend steady

Conditions are best on Tuesday.

  1. Today5217 Sept
  2. Fri5318 Sept
  3. Sat5519 Sept
  4. Sun5620 Sept
  5. Mon5721 Sept
  6. Tue5822 Sept
  7. Wed5623 Sept
Panthercap — botanical illustration

Panthercap

Amanita pantherina

Building58 today

Week's best 64 — on Mondayaverage 62by the weekend steady

Conditions are best on Monday.

  1. Today5817 Sept
  2. Fri6018 Sept
  3. Sat6119 Sept
  4. Sun6320 Sept
  5. Mon6421 Sept
  6. Tue6422 Sept
  7. Wed6223 Sept

Orange Birch Bolete

Leccinum versipelle

Building58 today

Week's best 65 — on Tuesdayaverage 62by the weekend rising

Conditions are best on Tuesday.

  1. Today5817 Sept
  2. Fri6018 Sept
  3. Sat6219 Sept
  4. Sun6320 Sept
  5. Mon6421 Sept
  6. Tue6522 Sept
  7. Wed6423 Sept

Been out in Istarska? Tell us how it went

No sign-up, five seconds. Reports are visible to everyone and help us check the forecast — where people say “nothing out there” and the model promises a flush, the model is wrong.

How much did you find?
When were you out?

This form does not ask for coordinates. What gets published is the name, the rating and the text — nothing else.

Common questions

Are there mushrooms in Istarska in September 2026?

Yes — conditions in Istarska in September 2026 are good, index 66 out of 100, with penny bun furthest along. That is a reading of weather, woodland and season: it does not promise you a full basket, but this is one of the weeks worth going out.

Which mushrooms are out in Istarska right now?

The species list for this region is built from confirmed records in GBIF. As soon as there are enough of them, the species appear here with their own forecast — we do not add a species to a region on a guess.

How is the index calculated?

An index from 0 to 100, built from the last month of weather, satellite woodland data, terrain and the seasonal window of each species. It is not a probability of finding anything: it is how well conditions match what that species needs.

When is the best day to go in Istarska?

Use the seven-day index on this page: pick the day with the higher number, and watch the flush phase — «Building» and «Peak» are the ones worth the drive. Today reads 66 out of 100.

The index is high but I found nothing — why?

The index reads weather and season — things that are the same for tens of kilometres around. It does not know your particular wood, and that is where the mushroom grows. The usual reasons: wrong trees — every species has its own, and no weather makes up for the wrong stand; the wood was felled recently or is young — the mycelium takes years to recover; the spot is picked out — everything near a road or a car park goes over a weekend; the flush has been taken — you came a day after those who came on time; or the flush passed and slugs and larvae got there first, which the model cannot see. The reverse holds too: a low index does not mean an empty wood. It means the conditions are against you, not that there is nothing there.

How the index is calculated, and what the model cannot promise — on the about page.