David G. Behrens and Carmona Behrens v. Mark Thomsen and Kimberly Thomsen

IN THE COURT OF APPEALS OF IOWA
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No. 25-0068
Filed February 25, 2026
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David G. Behrens and Carmona Behrens,
Plaintiffs–Appellees,
v.
Mark Thomsen and Kimberly Thomsen,
Defendants–Appellants.
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Appeal from the Iowa District Court for Benton County,
The Honorable Christopher L. Bruns, Judge.
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AFFIRMED
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Corey R. Lorenzen of Lorenzen Law Firm, P.C., Waterloo,
attorney for appellants.

Austin G. Collins and Phillip D. Klinger (until withdrawal) of Klinger,
Robinson & Ford, LLP, Cedar Rapids, attorneys for appellees.
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Considered without oral argument
by Tabor, C.J., and Ahlers and Langholz, JJ.
Opinion by Langholz, J.

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LANGHOLZ, Judge.

When it comes to property boundaries, being neighborly has its limits.
It is one thing to let your neighbors on your land to hunt or pass through
occasionally. But it is quite another to sit back and let them restore, develop,
maintain, and use your land for years on end under a false impression of
ownership. Taking that second course may invite Iowa law to step in and
create a new boundary line if you and your neighboring landowner recognize
and acquiesce—explicitly or implicitly—to the new boundary for at least ten
years. That happened here.

Mark and Kimberly Thomsen own land in Vinton. As a neighborly
gesture, they built a fence about thirty feet shy of the southern boundary, to
keep their livestock from grazing too close to their neighbors. But when new
neighbors—David and Carmona Behrens—moved into the southern plot,
the Behrenses mistakenly believed they owned everything up to the fence.
And they acted accordingly—clearing junk, planting and removing trees,
mowing, decorating, burying pets, and remedying storm damage. All the
while, the Thomsens did not disturb or intervene in their efforts. The
Behrenses’ uninterrupted use continued from roughly 1994 until at least
2016, when they learned they did not own the roughly half-acre of land south
of the fence. After unsuccessfully trying to resolve the boundary issue with
the Thomsens, they sued. The district court found the Behrenses proved
their boundary-by-acquiescence claim, and the Thomsens now appeal.

Our scrutiny of the record reveals that substantial evidence supports
the district court’s ruling. To be sure, the Thomsens point us to evidence
that cuts the other way. But under the governing standard of review, we only
ask whether substantial evidence supports the findings the district court
actually made. And through that lens, we find sufficient evidence that the

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Behrenses believed the fence was the property boundary and the Thomsens
implicitly acquiesced to their ownership for at least ten years. We thus affirm
and do not address the Thomsens’ other arguments that the court should
have reached and rejected the Behrenses’ two alternative claims for relief.

I.

The Thomsens bought a northern parcel of land in Vinton in 1985.
Soon after, they placed a fence about thirty feet from the southern boundary
line of their property. They chose the location because, at the time, they kept
livestock on the land and thought it was courteous to have a buffer between
the livestock and the adjoining property to the south. Indeed, the home on
the southern property is built near the boundary line, so they wanted to avoid
livestock grazing so close to their neighbor’s home. The land between the
fence and boundary line is a wooded, roughly half-acre rectangular parcel,
which the parties refer to as the “disputed property.”

In 1993, David and Carmona Behrens bought the southern property.
When they did so, they believed the fenceline was the boundary and that they
owned all the land up to the fence, including the disputed property. While
the legal description of the land excluded the disputed property, their pre-
purchase appraisal included it. So did their property taxes.

The property was a “disaster” when the Behrenses bought it. The
land was covered with horse nettles and trees, and it had a “large junk area
that extended into the disputed property that needed to be cleaned up.” So
right after moving in, they went to work clearing junk and restoring the land.
A year later, they installed a new septic system, which terminated into the
disputed property. And going forward, they generally maintained the
disputed property in the same fashion as the rest of their land, investing

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significant time and resources in its upkeep, particularly after two severe
storms. The Thomsens allowed this upkeep and improvement, never
interfering with or objecting to the Behrenses’ use or development of the
disputed property.

This state of affairs continued until 2016, when the Behrenses received
notice from the county assessor that they owned fewer acres than they
thought. The Behrenses raised the issue with the Thomsens, who said that
they had always known the boundary line in fact was beyond the fenceline.
Mark also told them not to worry about it, that they could keep using the
land, and he would not move the fence on them. And the Behrenses
continued to maintain the disputed property for several more years while also
trying to resolve the boundary issue with the Thomsens. But in 2021, the
Behrenses filed this suit, seeking to officially establish the fenceline as the
boundary either though adverse possession or statutory acquiescence under
Iowa Code chapter 650 (2021). In the alternative, they sought unjust-
enrichment damages from the Thomsens.

After a one-day bench trial, the district court entered judgment for the
Behrenses on their statutory boundary-by-acquiescence claim. It held that
the Behrenses treated the fenceline as the true boundary and that “[t]he
Thomsens’ silence in the face of the obvious use of the property by the
Behrens was acquiescence to the fence becoming the property line.” So the
court established the fenceline as the boundary between the parties’
properties. And it declined to reach the Behrenses’ alternative adverse-
possession and unjust-enrichment claims because they were moot.

After unsuccessfully moving under Iowa Rule of Civil Procedure 1.904
for the court to expand its ruling to reach and reject the two alternative claims
on the merits, the Thomsens now appeal.

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II.

Because boundary-dispute appeals are “heard as in an action by
ordinary proceedings,” we review for correction of errors at law. See Iowa
Code § 650.15; Ollinger v. Bennett, 562 N.W.2d 167, 170 (Iowa 1997). The
district court’s findings are akin to a jury verdict, and we will affirm so long
as they are supported by substantial evidence. Ollinger, 562 N.W.2d at 170;
Tewes v. Pine Lane Farms, Inc., 522 N.W.2d 801, 804 (Iowa 1994). And
viewing the record with an eye toward sustaining the district court’s findings,
we ask whether “the evidence supports the findings actually made,” not
whether substantial evidence could have supported a different outcome. Tim
O’Neill Chevrolet, Inc. v. Forristall, 551 N.W.2d 611, 614 (Iowa 1996); see also
Kaperonis v. Iowa State Highway Comm’n, 100 N.W.2d 901, 902 (Iowa 1960)
(noting the “heavy burden” under substantial-evidence review).

To create a new property boundary by acquiescence, a petitioner must
show clear evidence that the desired boundary “has been recognized and
acquiesced in by the parties” for at least ten straight years. Iowa Code
§§ 650.6, .14 (providing that if the court finds the new boundary has “been
so recognized and acquiesced in,” the boundary “shall be permanently
established”); Harvey v. Platter, 496 N.W.2d 350, 352 (Iowa Ct. App. 1992).
Acquiescence is “the mutual recognition by two adjoining landowners for ten
years or more that a line, definitely marked by fence or in some manner, is the
dividing line between them.” Vaudt v. Wells Fargo Bank, N.A., 4 N.W.3d 45,
49 (Iowa 2024) (cleaned up).

While both parties must ultimately “acknowledge and treat the line as
a boundary,” express recognition is not necessary—“acquiescence may be
inferred by the silence or inaction of one party who knows of the boundary
line claimed by the other and fails to take steps to dispute it for a ten-year

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period.” Ollinger, 562 N.W.2d at 170–71 (cleaned up). It may too be found
when “a person who knows that he is entitled to impeach a transaction or
enforce a right neglects to do so for such a length of time that, under the
circumstances of the case, the other party may fairly infer that he has waived
or abandoned his right.” Dwight v. City of Des Moines, 156 N.W. 336, 338–39
(Iowa 1916).

There is no real dispute that substantial evidence shows the Behrenses
believed and acted like they owned the disputed property. But acquiescence
“involves more than a mere establishment of a line by one party, and the
taking of possession by him.” Griffin v. Brown, 149 N.W. 833, 838 (Iowa 1914).
So the fighting issue here is whether substantial evidence supports the
district court’s finding that the Thomsens implicitly acquiesced to the
fenceline boundary for at least ten years. According to the Thomsens, they
always believed they owned the disputed property, they permitted the
Behrenses to enter and use the disputed property shortly after moving in, the
Behrenses’ use of the property was sparing until 2011, and they expressly
communicated their ownership in 2016, defeating any ten-year period of
acquiescence. But carrying forward the district court’s informed credibility
determinations, we find substantial evidence supports the court’s ruling.

The Behrenses openly developed the disputed property soon after
buying their property in September 1993—clearing junk and debris,
removing trees, and mowing. About a quarter of the junk area fell within the
disputed property, and the Behrenses cleared it over time without any
contribution or acknowledgment by the Thomsens. Although the Thomsens
indeed permitted the Behrenses to enter other parts of their land around this
time, that permission was limited to hunting pheasants in their cornfield.

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About a year after buying their land, the Behrenses installed a new
septic system. The project involved bulldozing a “shocking” number of trees
and changing much of the landscape, including in the disputed property. The
new septic lines terminated in the disputed area. Again, the Thomsens never
objected to or questioned the developments.

The Behrenses then continued to use the land in a way that exceeded
benign neighborly accommodations. Beyond regularly maintaining the plot in
the same fashion as the rest of their land, they buried the family dog on the
disputed property in 2002 or 2003. And they buried several more pets there
in the years that followed. For their part, the Thomsens rarely crossed over
the fence—no neighbor testified to seeing Mark in the disputed property.
And when Mark sprayed for weeds, he stopped at the fenceline.

But perhaps the clearest evidence of acquiescence came after a
derecho swept through central Iowa in 2011. The storm ravaged the
Behrenses’ property, and they hired workers to clear over ninety fallen trees,
some of which were in the disputed property. One worker spent two or three
weeks grinding stumps, and he worked up to the fenceline. The Thomsens
never suggested the storm damage within the disputed property was their
responsibility or otherwise contributed to the cleanup. After 2011, the
Behrenses continued to maintain the land—alerting the Thomsens to a dead
tree that threatened the fence in 2019 and clearing the storm damage after
the 2020 derecho. Again, the Thomsens never contributed or enforced their
rights.

In all, the Thomsens remained silent from at least 1994 to 2016 while
the Berhens restored, decorated, and developed the disputed property. That
degree of assent, for over twenty straight years, supports the finding the
Thomsens “waived or abandoned” their rights. Dwight, 156 N.W. at 338–39.

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And it aligns with similar cases finding implicit acquiescence. See Atkins v.
Reagan, 60 N.W.2d 790, 791–92 (Iowa 1953) (affirming boundary-by-
acquiescence claim because original owner knew the neighbors were making
material improvements within her land but chose not to “molest them in
their occupancy” for over ten years); Olson v. Clark, 109 N.W.2d 441, 445
(Iowa 1961) (finding party was on notice of the other’s use and claimed
ownership of property and nevertheless “remained silent for the statutory
period”).

“[A]cquiescence must, in large part, be determined in light of the
factual situation presented.” Tewes, 522 N.W.2d at 808. While the Thomsens
indeed offered “some evidence to the contrary, we defer to the trial court’s
interpretation of the facts because substantial evidence supports its finding
that” they knew of the Behrenses’ belief of ownership and opted to sit silent
for at least ten straight years. Id. We thus affirm judgment for the Behrenses.1

AFFIRMED.

1
The Thomsens also argue that the district court should have reached and rejected
the Behrenses’ two alternative claims: adverse possession and unjust enrichment. But
they do not meaningfully explain why the claims are not moot—as the district court
ruled—or why any exception to mootness applies. Because we affirm on the boundary-by-
acquiescence claim, any analysis of the merits of these others claims would be purely
academic. See generally Homan v. Branstad, 864 N.W.2d 321, 328 (Iowa 2015). So we
decline to address their merits.

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