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Medieval Household Pest Control

by: Paul Robertshaw <probertshaw@SCIENCEPHOTO.CO.UK>

In our modern sanitary environment, it's easy to forget that the medieval householder was engaged in a constant war against the encroachment of various vermin. The tiny invaders were given a helping hand by the rather unsanitary practice of covering the floor with layers of rushes. Given below are some of the suggestions that contemporary accounts made for dealing with pests. (SAFETY WARNING! Some of the herbs listed are VERY poisonous!!! Collecting endangered herbs is now illegal and not to be encouraged.)

Another thing to consider....Pest control was usually done by underlings rather than their literate employers. This means that there is not much in the way of written sources regarding vermin control. Some of the sources that I have used are from well before our period, however, earlier authors' work was copied down by scribes who often added their own suggestions, eg. the Palladius quotes are taken from an English MS of the early 15thC. However, I think that the information must still have been considered as worth writing down by people in the later middle ages.

I have tried to include only the herbs mentioned by him that would have been available in the l5thC (ie. no New World, Sub-Sahara African or Far East Asian plants). A final thought: all of the below are complicated ways of dealing with pests; I'm sure that squashing them is also a perfectly authentic activity!


Fleas are blood-drinkers, but are fairly fussy eaters, each species deliberately having their own preferred species to live on, however, they are wholly averse to taking a bite from anything they can land onto. Fleas seem to have been a common problem at the time, a problem exacerbated because no matter how clean people were, animals always provided a reservoir for fresh infection; even today, you are more likely to be bitten by a "cat flea" or "dog flea" than you are a "human flea". Once established in a house, fleas can be a difficult pest to remove as an adult can live up to 18 months between feeds. Unsurprisingly, fleas were a major problem, as this text from a late 14thC English manual of French/English conversation makes clear: 'William, undress and wash your legs, and then dry them with a cloth, and rub them well for love of the fleas, that they may not leap on your legs, for there is a peck of them lying in the dust under the rushes...Hi the fleas bite me so! and do me great harm, for I have scratched my shoulders till the blood flows'.

In concurrence, the G oodman of Paris (GoP, 1393) tells his wife that one of the ways to 'bewitch and bewitch again ' her 'husband to be' is to make sure that his bed is free of fleas during the summer. He comes up with various methods of dealing with these ' familiar beasts to men' : firstly he recommends the placing of flea-traps around the affected room: If the room be strewn with alder leaves, the fleas will be caught thereon '; I have heard tell that if you have at night one or two trenchers slimed with glue or turpentine and set about the room, with a lighted candle in the midst of each trencher, they will become stuck there'.

The GoP thoughtfully (in a different part of his book) tells us how to make glue: 'it behoves you peel holly when it is at the sap (whi ch is commonly from the month of May up to August) and then boil the bark in water until the topmost layer separate; then peel it off, and when it is peeled, wrap up that which remains in elder leaves or other large leaves, and set it in some cool place , as in a cellar, or within the earth, or in a cold dung heap for the space of nine days or more, until it is decayed. And the n behoveth it to pound it like brayed cabbage and to make it up into cakes like woad, and then go wash the cakes one after another, and break them up like wax; and let them not be too much washed in the first water, nor in too hard a water.

and after you may break it up all together and knead it in running water and put it in a pot and keep it well covered'. The great advantage of this glue is that it can be made whilst insect infestations are at their worst, ie. during the summer.

A 15thC English Leechbook (collection of medical recipes) suggests the following "traps": 'For fleas and lice to slay them, take horsemint and strew it in your house, and it will slay them' or 'Take the juice of rue and anoint your body with it' or 'Take gorse and boil it in water, and sprinkle that water about the house, and they will die. Palladius (5thC) recommended bring fleas to a sticky end on surfaces which were often sprinkled with oil dregs. John Gerard's Herball makes the following claims for: Fleabane (Erigeron sp.) 'burned where flies, gnats, fleas or any other venomous things are, doth drive them away' Fleawort (Plaintains or Plantago sp.) 'some hold that the herb strewn in the chamber where many fleas be, will drive them away, for which cause it took the name Flea wort: but I think it is rather because the seed does resemble a flea so much, that it is hard to discerne the one from the other'; Willow herb (Primilaceae or Lysimachia sp.), 'it is reported that the fume or smoke of the herbe burned doth drive away fleas and gnats and all manner of venomous beasts'

Ibn-el-Beithar, a 13thC Spanish Moslem writer, recommended macerating a cucurbit (Citrullus colycynthus) or oleander (Nerium oleander) in water and spraying the liquid around to get rid of fleas. If all of the above herbs proved ineffective, the GoP also had some hints for "direct- action":

When the coverlets, furs or dresses wherein there are fleas, are folded and shut tightly up, as in a chest tightly corded with straps, or in bag well tied up and pressed, or otherwise put and pressed so that the aforesaid fleas be without light and air and kept imprisoned, then will they perish forthwith and die...... The other way that I have tried [to catch fleas] and 'tis true: take a rough cloth and spread it about your room and over your bed, and all the fleas that shall hop on it will be caught, so that you may carry them away with the cloth wherever you will.. I have seen blankets [of white wool] set on the straw and on the bed, and when the black fleas hopped on, they were the sooner found upon the white and killed.'

This latter way of dealing with fleas seems to be corroborated by the duties of the Chamberlain in John Russell's 15thC Book of Nurture (as Russell meant the book to be used to teach male servants it's clear that outside, of the GoP's house, pest control is not just a female activity): 'Return in haste to your lord's chamber, strip the clothes off the bed and cast them aside and beat the feather-bed, but not so as to waste any feathers, and see that the blankets and sheets be clean'.

Nits and Lice

Fleas were not the only blood-suckers to afflict the population, the Leechbook had suggested a number of cures 'for nits in the head': [1] Make lye of wild nept (bryony) and therewith wash your head, & it will destroy them; [2] Take quicklime or piment [spiced wine], amd make powder of them, and mix the powder with vinegar and annoint the head with it. And this destroys them without falling of hair or any other harm; [3] Take seawater or else brine, and wash your head, and that shall destroy them; [4] Take the juice of a herb that is called blight, and annoint your head with it, and both lice and nits shall fall away.; [5] Take a broad list [strip of cloth] the length of a girdle, and annoint the one side with fresh grease mingled with quick-silver, and spread on it the powder of lichen and press on it with your finger so that it sticks firmly to it, and then fold it together, and sew together the sides; and then wind it in a linen cloth; and sew it together, and wear it henceforth; and the lice & nits shall die. This has been well proved. In 'Styrre Hyt Well', a collection of 15th century manuscripts found in Samuel Pepys' library, one recipe claims that 'to slay lice or nits. Take the herb broom and crush it and anoint them with juice and it will slay them'. Hortus Sanitus, a Venetian book from 1511 shows lice being brushed out of a man's hair. John Gerard's Herball claims that: cotton-weed or cudweed (Graphalium or Filago sp.), 'boiled in strong lees cleans the hair from nits and lice'. Palladius claimed that staveacre and cumin ground in wine and the juice of sour lupin would do the trick. To intercept gnats on their way to a human host, Palladius used oil dregs or soot from the fire in your room. Interestingly (in the light of the Leechbook's advice), he claimed that washing sheep in seawater would clear them of biting insects and allow their fleece to grow, though he never made the same claim for the riddance of human pests. Another way to slay fleas was the use of watered cucumber seed, ground cumin, lupine or 'psilotre' (probably psilothre or psiloter - Bryonia diocia) 'cast on the ground'.

Mosquitos and Gnats

More thirsty insects which required advice from the GoP: 'I have seen in diverse chambers, that when one had gone to bed they were full of mosquitoes,which at the smoke of the breath came to sit on the faces of those that slept, and stung them so hard, that they were forced to get up and light a fire of hay, in order to make a smoke so that they were forced to fly away or die, and this may be done by day if they be suspected, and likewise he that has a mosquito net may protect himself with it'. The Roman writer Pliny (1stC AD) suggested the burning of galbanum resin derived from the fennel plant. Galbanum, when mixed with sulphur was also recommended by Palladius as was fresh oil dregs, an oil dregs/ox gall mixture, a oil/ivy mixture, chamber soot or burnt waterleeches!. John Gerard thought that burnt fleabane or willow herb would drive off gnats, as would wormwood oil.


The medieval town environment was frequently none too sanitary (particularly the streets), and would have provided an ideal breeding ground for flies. The GoP comes to the rescue with some traps though: 'If you have a chamber or a passage where there is a great resort of flies, take little sprigs of fern and tie them to threads like to tassels, and hang them up and all the flies will settle on them at eventide; then take down the tassels and throw them out'.

Shut up your chamber closely in the evening, but let there be a little opening in the wall towards the east, and as soon as the dawn breaks, all the flies will go forth through this opening, and let it then be stopped up'.

Take a bowl of milk and a hare's gall and mix them one with another and then set two or three of these bowls in places where the flies gather and all that taste them will die.. otherwise have a linen rag tied at the bottom of a pot with an opening in the neck, and set that pot in the place that the flies gather and smear it within with honey, or apples, or pears; when it is full of flies set a trencher over the mouth and shake it'.

Take raw red onions and shred them and set it where the flies gather and all that taste them will die'.

These last two traps are similar to a "traditional" English remedy, which uses the fly agaric toadstool soaked in milk. John Gerard burned willow herb or fleabane to rid himself of flies. Ibn-el-Beithar recommended lacing meat with monkshood (very poisonous) or making a spray from the juice of oleander. More from the GoP: Have little twigs covered with glue on a basin of water'. This procedure requires a little elaboration on the technique outlined above for making glue: 'And he who would make glue for water, let him warm a little oil and therein melt his glue; and then lime his line'.

Have a string hanging soaked in honey, and the flies will come and settle on it and in the evening let them be taken in a bag'.

Direct action might be required on the part of the GoP though: Have whisks [little flat shovels rather like today's fly-swats] wherewith to slay them by hand...Have your windows shut full tight with oiled or other cloth, or with parchment or something else, so tightly that no f ly may enter, and let the flies that be within be slain with the whisk or otherwise as above, and no others will come in'. The GoP develops the "prevention is better than cure" policy hinted at in the above passage in another piece of advice: Finally it seems that flies will not stop in a room where there are no standing tables, forms, dressers or other things where they can set tle and rest, for if they have nothing but straight walls on which to settle and cling, they will not settle, nor will they in a shady or damp place. Therefore it seems that if the room is well watered and well closed and shut up, and if nothing is left lying on the floor, no fly will settle there.'

What's probably more likely is that flies will not stop in a room where untidy humans haven't been carelessly leaving bits of food lying around! The GoP also had a remedy for dealing with flies that afflict livestock too: Note that flies will never swarm on a horse that is greased with butter or with old salt grease. Not every means of getting rid of flies was used though: Caxton (reassuringly) lists flies as being 'beestes' unfit for human consumption in a French-English vocabulary.


Moths were a common enough problem in the Middle Ages, Lawrence Andrewe in the 15th Century wrote: 'The Motte breeds among clothes until they have bitten it into pieces and it is a maniable worm, and yet it hides itse lf in the cloth so that it can scantly be seen and it breeds gladly in clothes that have been in an evil air, or in a rain or m ist, and so laid up without hanging in the sun or other sweet air after'. Similar advice was given by the GoP: 'in order to preserve your fur coverlets it is apt often to air them, in order to prevent the damage which moths may do to them; and because such vermin gather when the cold weather of autumn and winter grows milder and are born in the summer, at such time you'd be advised to set out furs and stuffs in the sun in fair and dry weather; and if there comes a dark and damp mist that clings to you r dresses and you fold them in such condition, that mist folded and wrapped up in your dresses will shelter and breed worse vermin than before. Whereas choose a fine, dry day and as soon as you see heavier weather coming, before that it reachs you cause your dresses to be hung up under cover and shaken to get rid of most of the dust, then cleaned by beating them with dry rods '.

"Chemical warfare" was also the order of the day. Lawrence Andrewe advises that 'The herbs that are bitter and strongly smelling are good to lay among such clothes, as the bay leaves, cypress wood.' 'Styrre Hyt Well' says that 'to prevent damage by moths to clothes, take wormwood and rue and boil them in water and brush your clothes with the same water'.

The GoP suggested adding strong scents to clothes (but in this case it is not clear whether this is to deter moths or just to make clothes smell nice): 'The roses of Provence are the best for putting in dresses, but they must be dried and sifted through a sieve at mid-August so that the worms fall through the holes of the sieve, and after that spread it over the dresses'. John Gerard thought that the leaves and branches of cottonweed (or cudweed), golden mothwort (or cudweed) sweet trefoile, rosemary, wormwood and sea wormwood, 'being laid [separately] in warderobes and presses keepeth apparell from moths'. He also recommended sweet willow 'whole shrub fruit and all', shavings of wood and the resin from the cypress tree.

Palladius said that the best cure for 'prasocorides' [moths] was to wrap a sheep's stomach for two days around the place that the moths were breeding; after that time you could expect that 'there shall you find them heaped slain there'.

Rats and Mice

Medieval streets were usually strewn with household waste and the ordure of animals despite the attempts of civic authorities to combat such refuse (too large a subject to go into here). Such an environment was an ideal breeding ground for rodents, and these were a constant menace to provisions if they could establish themselves in a household: No sir, please God, for I make bold that you shall be well and comfortably lodged here [for there are no fleas nor bugs, nor other vermin], save that there is a great peck of rats and mice - Manual of French/English conversation, late 14thC.

Medieval rats were black rats. These have since been driven to extinction in Britain by their larger, more aggressive cousins the brown rat. Black rats have more of an affinity for living in homes than the browns, and less of a liking for sewers. It has been estimated that each medieval home had 2-3 black rats each supporting 4-5 fleas; black rat fleas are far less fussy about their choice of host than the strain of flea which lives on brown rats. It is easy to see why the Black Death spread so rapidly!

The Roman writer Pliny (who was held as a great authority on the animal kingdom during the Middle Ages) wrote that mice reproduced quicker than any other animal. The GoP gives advice in case 'rats are harming your corn, bacon, cheese and other provisions'.

Fortunately, the natural enemies of rodents could be employed, for example the GoP claims he controlled the vermin by 'by having a good array of cats. Such was the reputation of felines as hunters that during the 14-18th centuries, cat corpses with a dead mouse stuffed intheir mouth were sometimes built into the foundations of English houses as it was thought that this would deter other rodents from entering the premises.

Human "professionals" could also be employed, the GoP recommending the hiring of 'ratcatchers and mousecatchers'. So what techniques could people use? Why, 'by traps made of little planks upon sticks' (GoP) of course!

These brought rodents to a grisly end; a sight which might upset people of a delicate disposition, such as the Prioress in The Canterbury Tales Prologue:

She wolde wepe, if that she sawe a mous caught in a trappe, if it were deed or bledde

There is an illustration of a mousetrap in the right wing of Ingelbrecht's Annunciation Triptych by the Master of Flemalle c. 1425-1430

The GoP does not tell us directly what bait he'd use in a trap, but the ingredients in described in the following poisoned bait (without the toxic aconite) would seem to be suitable: 'Take an ounce of aconite , two ounces of fine arsenic, a quarter [of a pound] of pig's fat, a pound of fine wheaten [white] meal and four eggs, and out of these make bread and cook it in the oven and cut it into strips and nail them down with a nail'. Another poison that the GoP laid down included: 'cakes of paste and powdered aconite, setting these near to their holes where they have naught to drink'.

Failing that, follow this advice: 'If you cannot keep them from finding water to drink, it is good to cut up little pieces of sponge, and then if they swallow these and drink afterwards, they will swell up and die'.

Poisons were also popular amongst other writers. John Gerard recommended the use of the the root of hellebore 'in the weight of two pence' which 'kills mice and rats, being made up with honey and wheat flour'. Palladius used black hellebore mixed with fat, bread, cheese or flour.

Other options included the juice of bruised wild cucumber ('coloquynt') which 'slays the mice as diverse men have said'. A less complicated trap was to pour thick oil into a pan on which the rodent would be caught at night; Palladius claimed that the 'dregs may slay more than do your cats'.

Palladius also recommended blocking up the mouse holes with daffodils: 'They gnaw it out, but dead down shall they fall'. Nature, in the form of disease, could also be asked to lend a hand: if oak ashes were cast around the mouse-holes then a disease called 'the scabbe' could be expected to soon arise and kill the unfortunate rodents. Another plan was to make 'a smoke and stink' to drive off the rodents, suitable ingredients being hartshorn, goat's hooves, lily roots or galbanum.

Cockroaches and Weevils

Cockroaches and weevils seem to find grain, flour and other organic matter absolutely irresistable. As the staple food of humans was also cereals, the two populations were bound to come into conflict. Ibn-el- Beither recommended Planetre (Platanus sp.) to deal with cockroaches.

Pliny recommended dressing seeds with the ashes of a cat or weasel or steeping the seed in ox-gall. He also related how a toad fixed by one of its longer legs at the door would frighten weevils away. He also recommended storing the grain in airtight containers or in a pit, especially if the grain was covered in gypsum or chalk; this is a particularly effective solution as the granular material will ruin the insects' carapaces if they don't suffocate first.

Vinegar, salty fish or an unbaked brick soaked in water were also claimed by Pliny as weevil deterrents, as was the "heliotrope plant" (though the modern heliotrope is of New World origin). Palladius claimed that the cure for 'gurglions' [weevils] was coriander leaves placed on the floor and changed often; dried 'coniza' (probably conyse or flea-bane - Conyza sp. or Inula sp.) put under the grain was also deemed effective.


And on the subject of raiders of the larder, the GoP wrote that 'ants abound in a garden and if you cast sawdust of oaken planks upon their heap, they will die or depart at the first rain that falls, for the sawdust retains the moisture'. Pliny recommended painting bands around ants' nests.

The bands were to be made of either red earth and tar or oil dregs. He also point out that ants could be attracted to dried fish and destroyed. Palladius used vinegar and ashes mixed with red ochre whilst also claiming that burnt cockle shells or a mixture of origano and brimstone would if 'cast upon their hole...will make them flee'. Other measures of his included the ubiquitous oil dregs and soot, placing an owls heart on their nest, or placing chalk or the juice of 'rucul' (rocket) or 'syngrene' (horseleek) around the nest


More airborne pests that John Gerard dealt with using 'Fusseballs', a type of mushroom, which 'being set on fire kill or smother bees' Unfortunately I've not come across anything on wasps. However, the little blighters will quite happily drown themselves in a jar containing a mixture of honey and water - a method which I think would not look out of place next to some of the fly-trap designs outlined above.

Ecclesiastical intervention

Where infestations of pests became an epidemic, Mother Church sometimes invoked divine intervention to deal with the problem. Some examples from the late medieval period include: in 1479 Cockchafers indicted before the ecclesiastical court at Lausanne and condemned to banishment; in 1485 High Vicar of Valence comanded caterpillars to appear before him, gave them a defence counsel and finally condemned them to leave the area; in 1488 High Vicar of Autun commanded the weevils in neighbouring parishes to stop their attacks on crops and grain and excommunicated them.

Stupid medievals eh? It's more accurate to say that they were trying to find a way of curing something that they could observe without understanding why it was actually happening. Many pests go through a boom-bust cycle, the population increasing in size during one year and being markedly less the next year as their food runs out or the number of predators catches up. Once a plague of pests had reached bad enough proportions to warrant ecclesiastical attention, the epidemic was already on the wane. The intervention of the priests, and hence God too, seemed to have paid off. Nor was it just the medievals who performed such rites; though the practice later declined, the last such excommunication of pests took place as late as 1830 in Denmark.


1. The Goodman of Paris - M.E. Power; 2. The Constant Pest - George Ordish; 3. Herbal, or the History of Plants - John Gerard; 4. A Leechbook or Collection of Medical Recipes of the Fifteenth Century - Warren Dawson; 6. Palladius on Husbandry - Rev. B. Lodge (Early English Text Society); 7. Early English Meals and Manners - Frederick J. Furnivall (E.E.T.S.); 8. Dialogues in French and English - William Caxton (ed. H. Bradley, E.E.T.S.); 9. "Manual of French Conversation" in Revue Critique - Paul Meyer; 10. Styrre Hyt Well - Samuel Pepys with a foreword by Delia Smith; 11. A History of Herbal Plants (1977) - Richard Le Strange

Paul Robertshaw

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Last modified: Sun Dec 27, 1998 / Jeremiah Genest