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Newsletter of Penn Dutch Cow Care August 2010

Hi Folks,

Walking to survey pastures is not only healthy exercise but also educational and empowering
for you to manage a basic feed source more effectively. Walking through the areas where
cows will be (or where they have been) reveals some interesting facts. First, it lets you recognize
if a pasture is ready to be grazed or if it still needs rest time to grow more. Second, it
shows you what they ate and how much they leave behind. Third, it shows you what they
don’t eat at all.

Let’s consider what they do eat. Sorghum-sudan grass – a life saver for the hot and humid
weather we’ve had – is eaten well but somewhat unevenly, from a starting height of 20-30
inches down to about 10-12 inches high. Orchard grass bunches that are about 10-12 inches
high are usually eaten evenly down to about 5 inches. They love clover and if starting them
on it at 7-8 inches high with blooms, they will usually eat it fairly short – usually down to
about 3 inches. Fescue, while it grows during the heat when bluegrass goes dormant, is not a
preferred feed it seems. They don’t seem to eat it much if other green feed is nearby. I don’t
see too much timothy in any pasture, except for one permanent pasture which is somewhat
poorly drained. Rye grass is liked prior to it going to head, as with most grasses. Remember
that if orchard grass goes to head, it will have a poorer taste (due to internal chemical
changes) for the rest of the pasture season, even if you clip it after it’s headed out.

There are other plants that cows will eat that are not necessarily planted as forages. Cows eat
lambs quarters quite well and also smooth pigweed and burdock (burdock to a point). I’m
glad to see they eat these as it adds diversity to their diet. Undoubtedly, they eat little bits of
other plants as they wrap their tongues around their main target or they may nibble at them if
they are exposed to those species when the plant is young, perhaps early in the season when
first let out to pasture and desiring lots of fresh green herbage. I know they don’t eat thorny
plants like horse-nettle, bull thistle, Canada thistle and spiny red root pigweed. They also
don’t eat velvet leaf at all and its left behind to go to seed.

They don’t seem to search out and eat curly dock, purslane, narrow leaf plantain, common
plantain, common ragweed or giant ragweed, native chicory or dandelion either, at least from
what I have seen in numerous pastures over the last few months. I’m not sure if they eat wild
lettuce, I’ll have to keep an eye out for their like or dislike of it. This is a shame as some of
these plants technically have very good nutritional value (and all the ones named except for
the ragweeds are nice in small amounts in salads for us people). Pre-clipping a field 2-3
hours prior to setting cattle on it usually makes everything more palatable to the animals,
thus they take in the true variety of plants (all green matter) that is there. On average, I
probably see about 15-20 species of plants in my pasture walks, some of which I have not
yet identified.

With sorhum sudan, lambs quarters and smooth pigweed, you need to be careful not to set
animals on them right after the first rain following very dry conditions as these plants will
take up nitrates and become temporarily toxic. Sorghum sudan, though a wonderful forage
for high summer, can also be temporarily toxic with prussic acid if grazed to young.

Some plants you really don’t want your cows eating at all. Many grow in the hedge rows.
For instance, this year saw a bumper crop of poison hemlock. It looks like Queen Anne’s
Lace but much taller and has purple spots on its stem. It was everywhere in road side ditches
and the perimeters of fields. Pokeweed is growing well at this point, and will soon have its
well-recognized smooth shiny purple berries in about a month’s time.

At this point in the summer there is a lot of horse nettle growing. Horse nettle is easily found
in pastures, growing to about 12 inches high with small white flowers with a yellow center;
its stems and the undersides of leaves have small thorns. This is a poisonous plant, closely
related to deadly night shade. Deadly night shade has pretty little dark purple flowers and
has been growing for a few months now (usually near fences and old wood piles). Jimson
weed, another poisonous cousin to horse nettle and deadly night shade is a very obvious
plant, growing to about 3 feet tall, with large trumpet shaped light purple flowers.

I am a strong believer in clipping pastures to ensure good pasture management. I am not at
all sure I believe in what people are calling “tall grazing” if it means letting all kinds of
plants go to seed (and animals potentially getting pinkeye as their eyes water/tear - to which
flies are attracted - by poking through rank, mature growth as they try to get at the lush
growth underneath). If for no other reason, clipping will dramatically reduce un-wanted species
taking over a feed source which you need. More importantly, clipping also allows uniform
re-growth of your desired plants, allowing you to know when to put you cows back into
a pasture. Sorghum sudan can do an excellent job at re-growth when it is clipped, as it will
be very un-even in its height if un-clipped. While I think pre-clipping definitely has its place,
it should not be done if highly poisonous plants are observed in fields. (see photos)

Finally, a question: what is a weed? Having seen cows eat some plants generally thought of
as weeds, I would clarify the definition to only include plants that are poisonous in very
small amounts (photos) and thorny plants which cows will not touch and then go to seed
Fortunately cows do not normally ingest poisonous plants when normal pasture species are
available to graze. Practicing good pasture management is obviously good for cow health.


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