Amateur Gardening – 10 August 2019

16 AMATEURGARDENING 10 AUGUST 2019

F

ORthepastfewyears,theBest

BelovedandI havebeenmaking

a mini-meadowin themiddleof

theSpringCottagegarden.It’s

alwaysswingsandroundabouts.This

year,myhardyorchidsarepoor.Last

year,I hadmorethan 20 plantsandthis

yearI’mdowntosix.I thinkit was too hot

lastyear.Theorchidfoliage

shrivelledupearlysothere

wasn’tenoughenergyput

backintotheirbulbous

roots.I’mhopingthat

theymaybehavinga

yearoff.Ontheplus

side,though,theyellow

rattle(Rhinanthusminor)

hasneverbeenbetter.

Thisyearwe(well,

actually,theBestBeloved)

discovereda caterpillaron

bird’s-foottrefoil(Lotuscorniculatus).

Thislow-growinglegumegetsits

commonnamefromtheclaw-shaped

seedpods.It’salsocalledeggsandbacon

becausetheyellowflowershavea pink

tinge,andthere’splentyof it ontheverge

outsidethecottageandin themeadow.

Theslipper-shaped,yellowflowers

area goodnectarsourceforbees,

butit’salsoanimportantfoodplant

forcaterpillarsof thecommonblue,

silver-studdedblueandwoodwhite

butterflies.We’renotlikelytoseethelast

two at Spring Cottage, because they are

Val’smini-meadowareais attractinga varietyof insects

this year, including a six-spotburnetmothin themaking

bothPrioritySpeciesundertheUK

Post-2010BiodiversityFramework,

butwedogetcommonblues.

Ourcaterpillarwasa six-spotburnet

mothin themaking.Thevividcolourof

thecaterpillarandtheadultmothwarns

othercreaturesthatthey’renotpleasant

toeat,a processknownasaposematism

orwarningcolouration.Predators

sethatbrightlycoloured

nsdangeroustoeat,

etherit’stheblackand

ellowcaterpillarorthe

edandblackmoth.

Therearefiveand

ix-spottedburnetmoths

ndtheseday-flying

othsaredifficulttotell

art.I believetheonein

hotographaboveis a

burnetmoth(Zygaena

filipendulae). Here,it’sfeedingon

a fieldscabious(Knautiaarvensis). I

growthisin variouspartsof thegarden

because,likeallscabious,it’sgoodfor

pollinators.Burnetmothsarealsokeen

onknapweeds,ragwortandthistles.

I doallowknapweeds,but not generally

thistlesorragwort.

Thesix-spotis thoughttobethemore

commonof thetwomoths.Burnetmoths

havea secretweapon,besidestheir

brightlycolouredbodies.Theyareable

toproducehydrogencyanide– a

chemical compound that gives them a

TIP

Turningpartofyourlawn

intoa mini-meadowis a

goodearlyautumnproject.Plants

in theseedbankwillreturnoftheir

ownaccord,butit’salsoa good

timetoplantwildlifeplugs,and

youcanalsosowtheseedsof

annual yellow rattle now.

adtasteand,if eatenin largequantities,

theycankilla predator.Theyproduce

hydrogencyanideat everystage,so

I hopemycaterpillaris safefrom

munchingjaws.Bynowit mayhave

turnedintoa chrysalis,attaching itself

toa longgrassstem.

Therearenaturalvariationsin

wingmarkings,andscientistswanted

tofindoutwhetherdifferencesgavean

indicationof howtoxicanindividualmoth

mightbe.Scientistsat theUniversityof

Exeterexaminedthewingsof six-spot

burnetmothsusingultravioletlight,

whichis invisibletohumaneyesbut

visibletomanyof thebirdsthatpreyon

moths.Smallerandpalerredforewing

markingswereassociatedwithmore

cyanidein females.However,sizeand

brightnessof wingcolourwereno

guide to cyanide levels in males.

“Burnetmothsare

abletoproduce

hydrogen cyanide”

Day-fl ying six-spot burnet moths on fi eld scabious

Gardening We ek

with Val Bourne, AG’s organic wildlife expert

All photography Alamy, unless otherwise credited

TI Media

Bird’s-foottrefoilis animportantfood

plantforthecaterpillars of the common

blue butterfl y

A caterpillarofa six-spot

burnet moth

Thehardyorchids

in Val’smeadow

are poor this year

Val Bourne