^

PROJECT

TITLE:

Small

Grain

Variety

Testing

Under

Continuous

Cropping

Conditions

PROJECT

LEADER:

Jerald

W.

Bergman,

Superintendent,

MSU,

Eastern

Agricultural

Research

Center

_

OBJECTIVES:

To

determine

which

varieties

of

spring

wheat,

barley,

and

oats

are

most

adapted

for

production

under

continuous

cropping

conditions

MATERIALS

AND

METHODS:

The

experiments

reported

under

this

project

are

of

the

^

small

plot

replicated

nursery

type.

The

crop

rotation

order

is

spring

wheat,

small

grain

nursery

plots,

and

safflower.

A

herbicide

combination

of

bromoxynil

at

4.0

oz/acre

+

MCP

ester

at

4.0

oz/acre

is

applied

to

spring

wheat

and

the

^

nursery

plots

for

broadleaf

weed

control.

Treflan

herbicide

is

applied

preplant

and

incorporated

prior

to

safflower

planting

at

a

rage

of

0.75

or

1.0

lb.

active

ingredient/acre.

The

use

of

this

crop

rotation

and

chemical

weed

control

herbi

cides

has

been

very

effective

in

controlling

weeds

in

the

nursery

plots.

How-

^

ever,

volunteer

spring

wheat

has

been

a

problem

in

the

nursery

plots,

especially

during

drier

seasons.

The

experimental

site

was

fertilized

with

100

lbs.

of

ammonium

nitrate

(34-0-0)

on

November

10,

1987.

Two

tool

bar

with

harrow

operations

were

used

to

incorpo

rate

the

stubble

and

prepare

the

seedbed

for

planting.

The

small

grain

nur-

^

series

were

planted

on

May

22nd.

Total

moisture

received

during

the

crop

year.(September

1,

1987

thru

August

1988)

was

6.18

inches.

Moisture

received

and

mean

temperatures

during

the

grow-

^

ing

season

months

were

as

follows:

April

-

0.17

inches,

48.1°

^

May

-

0.79

inches,

64.2°

June

-

1.27

inches,

78.1°

July

-

0.92

inches,

73.7°

SUMMARY

OF

CROP

CONDITIONS:

Soil

moisture

conditions

were

very

poor

in

April

because

of

much

below

normal

rainfall

in

the

fall

and

winter

of

1987

and

little

^

early

spring

precipitation.

Dry,

hot,

windy

conditions

during

the

April

to

June

period

resulted

in

the

poor

emergence

and

eventual

plant

death

of

all

the

continuous

small

grain

variety

nursery

plantings

in

1988.

EXPERIMENTAL

RESULTS:

No

data

was

obtained

in

1988

due

to

crop

loss

from

the

extreme

drought

conditions.

m

FUTURE

PLANS:

Little

information

is

available

on

the

variety

performance

of

spring

wheat,

durum,

barley,

and

oat

varieties

grown

under

recropping

conditions.

The

results

of

these

small

grain

variety

nurseries

have

provided

eastern

Montana

growers

with

valuable

information

on

varietal

performance

of

spring

wheat, durum,

barley,

and

oat

varieties

on

recropping.

The

plans

are

to

continue

these

small

grain

variety

evaluations

under

recrop

conditions

in

1989.

At

the

time

of

this

writing,

25

inches

of

snowfall

with

1.53

inches

of

moisture

content

have

been

received

on

this

dryland

site.

Coupled

with

1.74

inches

of

precipitation

re

ceived

in

September

1988,

the

recrop

potential

has

greatly

improved

for

1989.