A - B - C - Ch - D - Dd - E - F - Ff - G - Ng - H - I - J - L - Ll - M - N - O - P - Ph - R - Rh - S - T - Th - U - W - Y

O

oak, 3:38

octopus, 15:17

Odontomyia hydroleon, see soldierfly

Oes Efydd, 14:31; 22:19

Oes Haearn, 22:19; 24:28

Oes Iâ, 13:29, 14:31; 24:39

Offa's Dyke by Jim Saunders, 23:43

offshore windfarms, 5:12

Ogwen, Afon/River, 1:37

ôl-adain gopor, Amphipyra pyramidea, 21:18

olew, 18:15

Oliver, Graham, 1:18; 24:8

ôl-troed ecolegol, 20:16

Oostvaardeplassen, 2:9

O'r Llain i'r Llestr 23:13

orchards, 12:37

Orchids of Britain & Ireland by Anne & Simon Harrap, 17:43

Orchids of the British Isles by Michael Foley & Sidney Clarke, 17:43

orchids, 4:28

ordoficaidd, 24:28

O'Reilly, Pat, 22:41

Ormerod, Steve, 9:4

Orthoptera, 16:16

     guide to, 16:21

Osmia parientina, see bee, mason,

Osmia xanthomelana , gweler gwenynen y glannau/ see bee, mason,

Osmunda regalis, 5:15-17 (c)

osprey, 12:4

otter, 1:45; 4:45; 6:43; 7:7; 9:34; 10:47; 12:45; 23:46

Otto, Ziggy, (Seigbert),  4:38; 18:47; 19:27; 21:34; 22:8; 23:4

Owen, Athro Hywel Wyn, 10:34(c)

Owen, Hugh, 7:12(c); 12:14(c)

Owen, Kath, 24:46

owl

     barn, 4:16; 5:36; 8:13; 14:40; 24:5ff

     little, 5:36

Oxwich, 18:25

oysterplant, 20:18

ozone, 13:36